Azure Active Directory Tutorial: Dynamic Groups 

You can assign role to the group by changing “Microsoft Entra role can be assigned to the group” to Yes. As soon as you switch that property, membership type is set to Assigned. So in short No, you can assign to dynamic group. If you have appropriate licensing, you could look into Access Packages with auto assigned policies, and you might be able to achieve this.

Replied to the same question.

You can edit the rule and add those users in a rule against UPN or mail NOT equals