Removable, qr stub axles are standard wheelchai components. A spring loaded ball bearing protrudes from the axle side and clicks into a detent in the axle socket. Pressing the button relieves the ball bearing and you just pul the wheel out. If you keep pulling, the axle just slides out from the cartridge bearing. Keep axles lightly greased to prevent binding, esp if you store the axle mounted.
Flatbed trailers with qr axles can flatpack for storage in a small space.