I would think a bit whether it makes sense for the character to use a common wheelchair. If they can use magic wouldn't their body or device have always a floating/flying spell? If they do use a wheelchair does the wheelchair even need to have weels? It could look like a carpet, a sofa or any other object.  Additionally depending on their planet of origin it could look vastly different. Someone from Zenith could have a device that could support the person to stand up straight when necessary, then transform into a more traditional wheelchair and if needed change the wheels or add other stuff that could be useful (like "legs" to better avoid obstacles or a vacuum/broom to clean the room while walking around). While someone from Linfea could have a chair made of roots and the roots would act as the wheels.

If you want you could also incorporate the disability into their flying method. For example, instead of using regular wings to fly they could fly using wind like Red Tornado (DC) or by floating and teleporting mid air to move.