My thought looking at her would not be jumping. Of course horses can surprise you by being mentally athletic and overcoming their physical challenges. But she is very steep, both shoulder and hindquarters, and has a long back and weak loin. I'd suspect she'd have a lot of difficulty getting her hind end underneath herself and even lower jumps would probably be a rough ride. I'm sure a young rider could walk, trot and canter around on her if she is sound, and do trails. A well fitting saddle might be tricky since she has low withers, a forward girth groove, and an upward slope to her back. From the photo a person can't tell if her barrel is flat sided or round; if it is flatter that would make things easier.