Making an isometric game by yourself is ambitious. I would just use Unity with Tiled or the built-in isometric support or Love2D with libraries personally. You could also mix in some 3D stuff to ease the burden.
You probably don't have shaders so you have fewer options for stuff like shadows and layering and blending tiles.
Most isometric engines have multiple layers. Infinity Engine had seven. This lets you fiddle with what is in front and behind. Things like circles around players feet require at least three layers (front half of circle, player, back half or circle).
I will
NEVER EVER use Unity for development. They are filthy scammers (I do use it for the convenience of minor maintenance tasks however). Woke Godot, etc and can also flush him/herself down the toilet.
I have trialed many engines and no engine that I tried, has come close in terms of isometric functionality for my needs. That's why I am doing what I am doing. Actually, in fact there isn't really a great amount of work remaining to do with the isometric engine aspect of things. I'm pretty happy with that as I mentioned in a previous post. I have moved onto planning, content creation, system design, and so on.