Openfire communication between servers

Good Morning

I have an OpenFire environment installed and configured through Active Directory named a.local. The company recently acquired a company, with its own Active Directory, b.local, and closed a site-to-site VPN and trusted relationship between ADs between the two companies.

Within this scenario is it possible to have the users of company B authenticate the openfire of company A? How to configure this?

Or would you have to install an OpenFire in Enterprise B and set up a communication between the two openfire? It is possible?

Would anyone have a solution for this environment?

Att Luiz

Note: A palliative solution would be to create the same users of company B in company A’s AD and point the Spark authentication server to the company, but then it hits a problem that when changing the passwords in company B the user can forget the password Which authenticates in Spark …

I tried to create a Local Domain group in domain of company A and put the users of Company B inside it, but OpenFire does not see the users of company B, only of company A.