You might consider asking your client what they want to work on, or maybe what you would want to work on if you were in a wheelchair. Sometimes we mistakenly assume that exercises have to be different in a wheelchair, and of to some extent they do, but a leg press is a leg press, a chest press is a chest press, a row is a row. We are not as limited as we allow ourselves to think we are.
There is a lot of information online, but here are some links which might help you with your search:
I hope this helps.