Wrist pain/swelling and constant need to "crack/pop" wrist after intraarticular distal radius fracture a year ago. Fracture healed; what can it be?

Ligaments. there is a good probability that your ligaments may be injured and an MRI would be in order to rule that out . Arthritis would be another reason.
Wrist problems. Following a fracture of the wrist with intra-articular component there can often be additional problems. The ligaments of the wrist may have been disrupted and, with continued use of the hand, are causing pain and swelling. Also, the wrist cartilage may have been damaged and are becoming inflamed. In any case, further imaging is needed to properly diagnose the underlying problem.