If I had to choose Id go with UO, but thats just me. It has the best gameplay of strategy jrpgs out there, and no, its not overrated. Theres a reason it had such a good reception in the community despite its very simple narrative and not particularly great characterization. It is that addictive. but thats me, ive always prefered an Ogre Battle-type gameplay than a Fire Emblem type gameplay, and this game satisfied me immensely.
Having that said, Ive also played Trails through Daybreak and despite not being particularly a fan of the Trails series (a series I consider C-Tier among jrpg franchises) this particular game is really good. Im waiting for the worldwide release of the sequel the next year. I disagree heavily with the notion that you need to play the other games to get into this one, this is a good entry point for anyone.
So If you are already into jrpgs id recommend getting both games if thats an option.
