Domain local or universal group?

I have 2 domains from 2 different forests.
Two way Trust between them.

Let say:

DomainA and DomainB

I need to add in local administrator group of server1.domainA users from DomainA and DomainB.

What the best practice?

Create a Domain Local group and add it in local administrator group of server1.domainA

Or

Create a Universal group and add it in local administrator group of server1.domainA