Wow starter can't box?

I just downloaded 4 wow starter accounts, was going to play with it for a week before getting new accounts going. It won't let me group starter toons, so no multiboxing until I buy accounts?

Trial accounts can't invite other players to a party. The inviter has to be a paid account. If you can get them grouped you can still multibox with trial accounts within the limits of the accounts themselves.

Here's a link to all the massive restrictions on trial accounts: https://us.battle.net/support/en/articl ... ccount-faq