Since your Azure tenant is going to be same, use the existing app.
Migrating to new Configuration Manager site

Hello!
In my company we have a working Configuration Manager environment with a primary site. We are planning on cutting over to a new SCCM we built in another data center that has a new site name and basically is a standalone MECm instance We currently have two working SCCM environments. One supports majority of the devices in the company and the new one targeting only few dozens test machines. My question is regarding Azure integration and using the Co-Management.
Our current SCCM has co-management enabled with Azure services connected and some machines being piloted for InTune. All devices are synced into Azure with Azure AD Connect and hybrid azure ad joined.
Before I do a full cutover, can I enable Azure integration in my new SCCM environment? Meaning, can I create a new server app, client app, CMG and co-management? Will it break anything in the current configuration manager environment?
Regards
Jakub