I use
FuBar_RestFu which is only on CurseForge, on my Classic and Retail accounts and it works great. It shows most of the info you need about your toons including how much rested the toon is and how much XP the toon has. Along with where the toon is, the faction, and the class. I might be missing other info, but this is off the top of my head.
Cheers!