Beginner's questions

[taas42]

Hi!

I'm relatively new to this game (play about 1 month).
I have the following setup for pvp:
- PoM Eddie
- Osiris
- Sekhmet
- The Prisoner

Questions:
- I use echo talisman on Sekhmet. Is it worth?
- May I use Immortal talisman on PoM Eddie? Or on some other toon?
- May I change Prisoner to one of the Liliths? If yes, which one?
- Bonus: what are the best talismans for the toons above? :)

Thanks in advance!
taas42