Can a misaligned second molar be fixed?

In your case Invisalign ortthodontics would be by far the best solution. Invisalign always includes the second molars as opposed to traditional wire and bracket Orthodontics which almost never includes the seconde molars.  Invisalign is faster, more comfortable, and a healthier orthodontic technology than traditional wire and bracket orthodontics.  Although I do not know all the details of your situation,  I would advise that you get an opinion from a General Dentist who has a lot of experience with Invisalign Orthodontic treatment before you proceed.  Crossbites are very much more easily corrected using Invisalign than traditional orthodontics because the aligners eliminate the interferences during movement of the teeth.  At Wilton Dental Associates, CT we have been doing this for 22 years.