so I pulled some Focus units...

Made a post with others posts where you can read about the IV's of Owain and Ophelia:

https://fireemblem.gamepress.gg/q-a/everyone-asking-about-owain-and-ophelia-ivs

I'd keep Ophelia for future merges and fodder the rest. If you don't have plans to eventually make a super-merged Ophelia, you can fodder her like any other 5*.

I actually like the -SPD on Owain to force more enemy attacks. You can make him a defensive enemy phase tank with Steady Stance 4 and Quick Riposte seal. That said, I think giving up such good fodder is a bit poor. Up to you, but if you like him you can certainly make him work.

Overall though, building units you love should take precedence over anything else since powercreep will always exist as long as this game does.

Owain has decent ivs so keep him unless you want wrath. Ophelia... Oof. Chill Res byeeeeeeee