Is delta petlil/lilligant (fire) useful at E4?

I am asking this because as of now i have an azumarill but she sucks coz all the moves except bubble beam have an accuracy of less than 100 and it only knows one fairy move , but one good thing is that it has thick fat ability and is a damage soaker. So should i switch it with delta petlil/lilligant or not?

I definitely think that Delta Petilil/Lilligant (Water) is a great pick. It has a unique typing, solid STAB attacks, and access to Tail Glow is fantastic. I’d definitely go for that over Azumarill if it has Thick Fat, as Huge Power is Azumarill’s best ability.

if i switch out azumarill, the fairy type from my team is gone so then can i choose togekiss as an alternate fairy type? since choosing petlil will also make me switch out my charizard bcoz other wise i will have 2 fire types.

That will probably work, just make sure you know how to use both of them.