Question about adding VEs to existing physical appliance device group without ASM licenses

We're in the process of migrating our old physical appliances to virtual appliances. I'm at the point of adding the new VEs to the existing device group. Our physical appliances have ASM licenses, but we don't have ASM licenses for the VEs yet. Management is still in discussion about on-prem licenses or distributed cloud services. 

When attempting to sync the new VEs, I get a sync error for 'ASM feature not licensed'. 

Do I need the ASM license to sync these together, or is there another method I can use? The new VEs aren't in the ASM device group.

If I need the license, would a trial license work momentarily?  

If they decide to opt for the distributed cloud services, what are my next steps to getting these appliances synced?