Azure Active Directory Domain Services - Access to Resources in On-Prem Active Directory

Our current infrastructure uses on-prem active directory which synchronizes to Azure using AD Connect. The plan is to also add Azure Active Directory Domain Services in addition to this.

From what I have looked into, it seems that when this is configured we will have a separate domain which we ideally need to name as a subdomain of our current one. We are then going to deploy Microsoft Virtual Desktop to this domain and the user’s will be authenticating with their on-prem credentials when they access the virtual computers which I understand should work if on-prem syncs to Azure AD and then Azure AD to Azure ADDS.

In this scenario what if the virtual desktop sessions need access to resources in the on-prem domain? Would we need to set up a trust or would it automatically be able to reach them?

Thanks and sorry for this noob question as I’m new to infrastructure.