I pick OT.

I just don't like SRPGs, so it's all down to personal preference

Triangle Strategy. Love the genre and story is interesting enough. Something in OT doesn't click with me, but they both are great.

I prefer Octopath because it brings a bit of fresh air in the RPG genre with its deep, varied, well told 8 characters stories and the goodness of its turn-based combat gameplay. What it lacks is maybe a true ending that strongly bound all characters destiny together, although there is some sort of a final battle, yet optional.

I also really appreciated Triangle Strategy, as a fan of SRPG, but not fell in love with the too many choices the story gives you, since in the end they bring the story to an overall conclusion that is partially good. I missed the golden route just for a single choice made, what is considered the true good ending, so maybe I will replay it at a later time. However, I feel this game is "just a step" behind the kings of this genre, Final Fantasy Tactics and Tactics Ogre: Let Us Cling Together.

Anyway, they are both great games worth playing.

Unlikley as these games are made for the people demanding Square make turn based FF and FF Tactics games again. This is their answer.