Merge Ffortnite Account?

I want to merge my main account with a 2 account only if I try it I must be connected with my 2 account with Nintendo, that goes if I connect now with an account on the switch then that, and how long takes mergen

If one account is on the switch, the other must be on PS4. Otherwise it is not stupid. And the merge takes 2 weeks.

Yes my main account is on the ps4 and the other one I have to sign on the switch

Oh, right. Then it will not work. You would have the one account before Season 5 connected to the switch.