Hello A S,
Thanks for your question.
Yes, the two can co-exist, as long as they are not syncing the same objects to the same tenant. Ensure both are configured to handle different objects or attributes to avoid conflicts
See below:
https://learn.microsoft.com/en-us/entra/identity/hybrid/cloud-sync/tutorial-pilot-aadc-aadccp
Also, take a look at the comparison of both. This will help you determine what to sync:
https://learn.microsoft.com/en-us/entra/identity/hybrid/cloud-sync/what-is-cloud-sync#comparison-between-azure-ad-connect-and-cloud-sync
Please let me know if you have further questions**
You can mark it 'Accept Answer' if this helped.