I seem to remember reading you enjoyed the Assassin’s Creed series. You could try Assassin’s Creed Odyssey. It is a little more of an action open world rpg but it is fairly fun. I think you’d enjoy it. If you like turn based games I’ve heard loads of good things about Slay the Spire which LED recommended. Also Elder Scrolls Skyrim is a modern day classic as Mr3rdrock suggested.
I myself play Isometric RPG games on PC such as Pillars of Eternity 1 and 2. I don’t know if I’d recommend them right off the bat. They’re a bit of an acquired taste in terms of gameplay. Not super action based. More strategy is involved in those. Also if you look into them, expect to read a lot at least for the first one. The second one has more voice acting as well as a simpler turn based mode many have said is fun. Both games take over 40 hours to complete.
For you I’d go with Assassin’s Creed Odyssey if you haven’t tried it already. Just maybe look into buying a controller for your PC if you don’t already have one.