And thats the problem!
Outdoors needs all the things that a portable or folding chair avoids because of the fact that its portable. It must be light.
So... Suspension, bigger wheels, proper sized pneumatic tyres, bigger chair able to support real batteries, more supportive seating, which are all heavier and bigger but needed for more comfort/stability speed and more power for hills and for range. And bigger frame and physical size to carry all the heavier stuff... Means its no longer portable.
So. Thats the compromise.
So you have to accept a few issues. But look for bigger lithium battery alloy frames, and so on. But with all the above stuff too. There may be better chairs - slightly. But the real question is what compromises are you prepared to make. But I never saw any portable chair that I would consider stable and adequate for outdoor use. My chair here does not fold, and has everything you want for outdoors in comfort and will do the hills. And fancy seating. Its also 185kg. And still 120kg with no fancy seating.