If I want to recuit ironman, cobolt man,
do I need both a thunderbolt and an avenager in order to recuit him since he has loyality and u need a avenger to recuit him?

Yes. Loyalty means you've got to share an affiliation out of the field. Normally, that'll mean you need a Thunderbolts character along with an Avenger. There are cases, like Clone Saga and Sinister Six, where Loyalty can be met with a non-Thunderbolt, but you must ALWAYS have an Avenger on the field for him.