Vaike!Owain- B good mods for a physical unit overall, but the classes he gains are somewhat limited. but at least he has no negative mods. he can use magic, but it would probably still be better to use him as a physical fighter.
Stahl!Owain-B even if he doesn't have any negative mods, his mods are still not that good. As for his classes, they are okay but not great, but at least he gets Luna and Aegis. This probably isn't the best pairing, but it isn't the worst.
Vaike!Owain: B, probably the best option if you want Owain to be physical, though he can still do magic as well which is why I think Dread Fighter was made for this pairing. Owain will pretty much only get Sol but he already has a great list of skills in the first place, so all he'll need are the right mods.
Stahl!Owain: Access to Renewal, Counter and GF would make Owain a good sniper, and if not you've still got DG+ and Luna. Not one of Stahl better options but still workable, B.
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