For people who don't have the GOTY EDITION. Telltale gives you a liltle snippet of how Clem gonna play in the Making of. So here's the information I'll gotten.
•No one is replacing Lee
•Clem fighting style is different from Lee's. She's more of a scrabbler(escapist) who uses the environment alot more instead of brawn. She no Michonne
•"We heard alot of people say if we gonna play as Clem in season 2 you better not hurt her remember shes in Robert Kirkman's zombie world the player is pretty much the only thing she's got going for her"-Kevin Bruner