So, I played some mix and match. I located all the data that used to be in spell.dbc from WOTLK, and matched it to its cooresponding legion db2. Here are the locations!
*All but 3 columns are still contained in the DB2s
* unk_320_2 and unk_320_3 are, for obvious reasons, no longer contained within the DB2s
* SpellRuneCost was removed in Legion, therefor column RuneCostID does not exist
* All types of spell costs were merged into the Manacost column in SpellPower.db2. (Energy, Runes, Mana, Rage, Runic Power, etc.)
* The singlle hardest DBC to determine the correct column IDs for is spelleffect.db2. Almost all of the rest contain VERY similar data, and was just a case of double checking enough data to be sure you had the correct column, but spelleffect contains all the dmg modifiers and whatnot, which have almost entirely been changed since WOTLK for almost every spell. That was not fun, and is one of the reasons I am hesitant to actually supply the columns within the DB2s. Every other DB2 I'm 100% confident in my definitions, but I am only about 75% with my defintions of SpellEffect. I AM, however, 100% confident that every column I listed in the table below is correctly connected to its DB2 counterpart.
ID - Spell
SpellCategory - SpellCategories
DispelType - SpellCategories
SpellMechanic - SpellCategories
Attributes - SpellMisc
AttributesEx - SpellMisc
AttributesEx2 - SpellMisc
AttributesEx3 - SpellMisc
AttributesEx4 - SpellMisc
AttributesEx5 - SpellMisc
AttributesEx6 - SpellMisc
AttributesEx7 - SpellMisc
Stances - SpellShapeShift
unk_320_2 - Always 0
ExcludedStances - SpellShapeShift
unk_320_3 - Always 0
Targets - SpellTargetRestrictions
TargetCreatureType - SpellTargetRestrictions
SpellFocusObject - SpellCastingRequirements
FacingCasterFlags - SpellCastingRequirements
CasterAuraState - spellaurarestrictions
TargetAuraState - spellaurarestrictions
CasterAuraStateNot - spellaurarestrictions
TargetAuraStateNot - spellaurarestrictions
CasterAuraSpell - spellaurarestrictions
TargetAuraSpell - spellaurarestrictions
ExcludeCasterAuraSpell - spellaurarestrictions
ExcludeTargetAuraSpell - spellaurarestrictions
CastingTimeIndex - SpellMisc
RecoveryTime - SpellCooldowns
CategoryRecoveryTime - SpellCooldowns
InterruptFlags - SpellInterrupts
AuraInterruptFlags - SpellInterrupts
ChannelInterruptFlags - SpellInterrupts
ProcFlags - SpellAuraOptions
ProcChance - SpellAuraOptions
ProcCharges - SpellAuraOptions
maxLevel - SpellLevels
BaseLevel - SpellLevels
SpellLevel - SpellLevels
DurationIndex - SpellMisc
PowerType - SpellPower
ManaCost - SpellPower
ManaCostPerLevel - SpellPower
ManaPerSecond - SpellPower
ManaPerSecondPerLevel - SpellPower
RangeIndex - SpellMisc
Speed - SpellMisc
ModalNextSpell - SpellClassOptions
StackAmount - SpellAuraOptions
Totem1 - SpellTotems
Totem2 - SpellTotems
Reagent1 - SpellReagents
Reagent2 - SpellReagents
Reagent3 - SpellReagents
Reagent4 - SpellReagents
Reagent5 - SpellReagents
Reagent6 - SpellReagents
Reagent7 - SpellReagents
Reagent8 - SpellReagents
ReagentCount1 - SpellReagents
ReagentCount2 - SpellReagents
ReagentCount3 - SpellReagents
ReagentCount4 - SpellReagents
ReagentCount5 - SpellReagents
ReagentCount6 - SpellReagents
ReagentCount7 - SpellReagents
ReagentCount8 - SpellReagents
EquippedItemClass - SpellEquippedItems
EquippedItemSubClassMask - SpellEquippedItems
EquippedItemInventoryTypeMask - SpellEquippedItems
Effect1 - SpellEffect
Effect2 - SpellEffect
Effect3 - SpellEffect
EffectDieSides1 - SpellEffect
EffectDieSides2 - SpellEffect
EffectDieSides3 - SpellEffect
EffectRealPointsPerLevel1 - SpellEffect
EffectRealPointsPerLevel2 - SpellEffect
EffectRealPointsPerLevel3 - SpellEffect
EffectBasePoints1 - SpellEffect
EffectBasePoints2 - SpellEffect
EffectBasePoints3 - SpellEffect
EffectMechanic1 - SpellEffect
EffectMechanic2 - SpellEffect
EffectMechanic3 - SpellEffect
EffectImplicitTargetA1 - SpellEffect
EffectImplicitTargetA2 - SpellEffect
EffectImplicitTargetA3 - SpellEffect
EffectImplicitTargetB1 - SpellEffect
EffectImplicitTargetB2 - SpellEffect
EffectImplicitTargetB3 - SpellEffect
EffectRadiusIndex1 - SpellEffect
EffectRadiusIndex2 - SpellEffect
EffectRadiusIndex3 - SpellEffect
EffectApplyAuraName1 - SpellEffect
EffectApplyAuraName2 - SpellEffect
EffectApplyAuraName3 - SpellEffect
EffectAmplitude1 - SpellEffect
EffectAmplitude2 - SpellEffect
EffectAmplitude3 - SpellEffect
EffectMultipleValue1 - SpellEffect
EffectMultipleValue2 - SpellEffect
EffectMultipleValue3 - SpellEffect
EffectChainTarget1 - SpellEffect
EffectChainTarget2 - SpellEffect
EffectChainTarget3 - SpellEffect
EffectItemType1 - SpellEffect
EffectItemType2 - SpellEffect
EffectItemType3 - SpellEffect
EffectMiscValue1 - SpellEffect
EffectMiscValue2 - SpellEffect
EffectMiscValue3 - SpellEffect
EffectMiscValueB1 - SpellEffect
EffectMiscValueB2 - SpellEffect
EffectMiscValueB3 - SpellEffect
EffectTriggerSpell1 - SpellEffect
EffectTriggerSpell2 - SpellEffect
EffectTriggerSpell3 - SpellEffect
EffectPointsPerComboPoint1 - SpellEffect
EffectPointsPerComboPoint2 - SpellEffect
EffectPointsPerComboPoint3 - SpellEffect
EffectSpellClassMaskA1 - SpellEffect
EffectSpellClassMaskA2 - SpellEffect
EffectSpellClassMaskA3 - SpellEffect
EffectSpellClassMaskB1 - SpellEffect
EffectSpellClassMaskB2 - SpellEffect
EffectSpellClassMaskB3 - SpellEffect
EffectSpellClassMaskC1 - SpellEffect
EffectSpellClassMaskC2 - SpellEffect
EffectSpellClassMaskC3 - SpellEffect
SpellVisual1 - SpellxSpellvisual
SpellVisual2 - SpellxSpellVisual
SpellIconID - SpellMisc
ActiveIconID - SpellMisc
SpellPriority - Set to 0
SpellName0 - Spell
SpellName1 - Always Empty
SpellName2 - Always Empty
SpellName3 - Always Empty
SpellName4 - Always Empty
SpellName5 - Always Empty
SpellName6 - Always Empty
SpellName7 - Always Empty
SpellName8 - Always Empty
SpellNameFlag0 - Always 0
SpellNameFlag1 - Always 0
SpellNameFlag2 - Always 0
SpellNameFlag3 - Always 0
SpellNameFlag4 - Always 0
SpellNameFlag5 - Always 0
SpellNameFlag6 - Always 0
SpellNameFlag7 - 16712190
SpellRank0 - Spell
SpellRank1 - Always Empty
SpellRank2 - Always Empty
SpellRank3 - Always Empty
SpellRank4 - Always Empty
SpellRank5 - Always Empty
SpellRank6 - Always Empty
SpellRank7 - Always Empty
SpellRank8 - Always Empty
SpellRankFlags0 - Always 0
SpellRankFlags1 - Always 0
SpellRankFlags2 - Always 0
SpellRankFlags3 - Always 0
SpellRankFlags4 - Always 0
SpellRankFlags5 - Always 0
SpellRankFlags6 - Always 0
SpellRankFlags7 - 16712188
SpellDescription0 - Spell
SpellDescription1 - Always Empty
SpellDescription2 - Always Empty
SpellDescription3 - Always Empty
SpellDescription4 - Always Empty
SpellDescription5 - Always Empty
SpellDescription6 - Always Empty
SpellDescription7 - Always Empty
SpellDescription8 - Always Empty
SpellDescriptionFlags0 - Always 0
SpellDescriptionFlags1 - Always 0
SpellDescriptionFlags2 - Always 0
SpellDescriptionFlags3 - Always 0
SpellDescriptionFlags4 - Always 0
SpellDescriptionFlags5 - Always 0
SpellDescriptionFlags6 - Always 0
SpellDescriptionFlags7 - 16712188
SpellToolTip0 - Spell
SpellToolTip1 - Always Empty
SpellToolTip2 - Always Empty
SpellToolTip3 - Always Empty
SpellToolTip4 - Always Empty
SpellToolTip5 - Always Empty
SpellToolTip6 - Always Empty
SpellToolTip7 - Always Empty
SpellToolTip8 - Always Empty
SpellToolTipFlags0 - Always 0
SpellToolTipFlags1 - Always 0
SpellToolTipFlags2 - Always 0
SpellToolTipFlags3 - Always 0
SpellToolTipFlags4 - Always 0
SpellToolTipFlags5 - Always 0
SpellToolTipFlags6 - Always 0
SpellToolTipFlags7 - 16712188
ManaCostPercentage - SpellPower
StartRecoveryCategory - SpellCategories
StartRecoveryTime - SpellCooldowns
MaxTargetLevel - SpellTargetRestrictions
SpellClassSet - SpellClassOptions
SpellClassMask1_1 - SpellClassOptions
SpellClassMask1_2 - SpellClassOptions
SpellClassMask2 - SpellClassOptions
MaxAffectedTargets - SpellTargetRestrictions
DefenseType - SpellCategories
PreventionType - SpellCategories
StanceBarOrder - SpellShapeShift
EffectChainAmplitude1 - SpellEffect
EffectChainAmplitude2 - SpellEffect
EffectChainAmplitude3 - SpellEffect
MinFactionID - SpellCastingRequirements
MinReputation - SpellCastingRequirements
RequiredAuraVision - SpellCastingRequirements
TotemCategory1 - SpellTotems
TotemCategory2 - SpellTotems
RequiredAreaGroupId - SpellCastingRequirements
SchoolMask - SpellMisc
RuneCostID - Doesnt Exist
SpellMissileID - SpellVisualMissile
PowerDisplayId - SpellPower
EffectBonusMultiplier1 - SpellEffect
EffectBonusMultiplier2 - SpellEffect
EffectBonusMultiplier3 - SpellEffect
SpellDescriptionVariableID - Spell
SpellDifficultyID - SpellCategories
I haven't finished all the auxiliary DBCs, and to be perfectly honest I know with the amount of changes, additional animations, etc. etc. etc. it probably is entirely impossible to get the new data running, but this is the type of thing that keeps me busy when I'm really bored, so I'm going to write the DBCs anyway and see what happens. I'm currently working on the related DBCs to spell.dbc, but those are more a case of rearranging values.
