Input detection, sure, but even “no engine” games use standard input detection libraries, like SDL. I’m guessing the games you listed likely use the same library for that, and the behavior is probably identical to what Unreal, Godot, and Unity do. There’s pretty much no “feel” here.

I’ve built games, I’m pretty familiar with what they offer here. Input detection just abstracts over hardware differences, so you can check if they pressed “A” instead of knowing that’s “controller button 7” or whatever. Most games will still interpret that manually (e.g. if “A” is “jump,” apply X force upward for the physics system).

Physics is highly tuned by the developer, regardless of what abstraction they use, especially for simpler games where physics isn’t really a thing (e.g. older FF games just had simple object detection). You can achieve pretty much any feel you want with any of the standard physics engines, especially for simpler interactions like platforming.

There’s no reason I couldn’t build a convincing reimplementation of FF or Secret of Mana in Godot, Unreal, or Unity. Generally speaking, that’s not the goal.