If you decide to let ASR deploy the mobility agent for you and depending the OS you want to replicate, you will need to provide two more credentials. One for Windows Machines and another one for Linux machines.
Another solution would be that you deploy the Mobility agent using another solution such as System Center Configuration Manager (SCCM) or any other deployment method.
For a migration project (not a Disaster Recovery), you also have another options to Migrate the VMs from VMware that is not using ASR and which is Agentless. You will find a comparison on the following link:
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