Thank you for posting your query on Microsoft Q&A. I am reviewing this and will get back to you with further inputs.
From above description I was able to understand that you are looking for a way to manage SAAS application hosted on Azure/AWS public cloud via Microsoft Entra Global secure access.
Update:
Thanks for your time and patience, after checking thoroughly I came to know that this is a known limitation. At this time, remote networks can only be assigned to the Microsoft 365 traffic forwarding profile.
Thanks,
Akshay Kaushik
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