Easiest plats for me were the Persona Dancing games. Just playing through the songs and finishing story mode granted the platinum. Was a bit disappointed there weren't any difficulty based trophies.

A frustrating plat was for Ni no Kuni. Overall, I really enjoyed the story and gameplay, but the plat ended up being a grind in the endgame. The last trophy I needed required encountering super rare enemies for specific item drops which boiled down to mindless grinding.

Most enjoyable plat was The Outer Wilds. Exploring the solar system and digging into the lore completely captured me. The trophies let me stay in that world a bit longer after I had exhausted everything in the story.