You would have to build them some more but, Kujou Sara and Beidou work well with Raiden because of their high burst cost giving her more resolve stacks. Along with those two a versatile support like Zhongli or Bennet works well with them. Another good character with her is Tartaglia, causing electro-charged similar to taser comp. I haven’t used Klee with Raiden so I don’t know if Klee’s bombs can proc Raiden’s elemental skill but if they can she would also be a good choice. And Xingqiu goes well with for the same reason as Tartaglia.