If I were to nitpick it would just be the texture on the spikes on his shoulders, gauntlets, and left handed weapon (maybe boots too) they need to be different from the armor.
As far as I know, there's absolutely no problem; insofar as the Author of the work you're using is OK with it.
We were just talking the other day about why no one seems to use the custom animation sets found on the Hive, and just constantly re-uses in-game animations; same argument could be said for geomerging.
I don't know about "realistic", but if you're going for Wc3-styled, have you studied the way they do some of the classic human Hero faces (like Paladin/Uther, Archmage, Mountain King/Muradin, etc)?
I rather call him "Ganondorf". That's his true name. Ganon is his Demonform. I don't know why people tend to just call him Ganon.
Mostly because it’s an abbreviation, that was my intention when typing that. I forget that there actually IS a Ganon.
I’ll use those pictures as reference.
What wc3 units face matches closest to Ganondorf’s face proportions?
A mix in between. He’ll use the sword in alternate animations
How about like in Hyrule Warriors: He uses the Sword for his more brutal bloody attacks and his Sorcery for the rest of the undeserving Weaklings. When i think of Ganondorf with the Spirit of Demise within him i think this describes OoT Ganondorf the most.
You could give Ganondorf his Trident in his Alternate animations.