Hi @Anonymous Thank you for posting your question on Microsoft Q&A and for using Azure services.
My understanding is that you are asking about the possible latency if having Java APPs on AWS and SQL DB in Azure.
Latency might not be the biggest problem, even though it should be carefully measure upfront, as - depending on application architecture – can really have a huge impact on performances. One thing to keep in mind that usually network IO done in the same cloud, in the same region, is free. Moving data from one cloud to another will definitely incur in extra costs, as Network IO will most likely be billed both for ingress and egress.
We would strongly recommend the impact of network io costs before starting any migration.
Also, OpenShift is available on Azure as well https://azure.microsoft.com/en-us/products/openshift/#overview
Please let me know if you have additional queries. I will be more than happy to assit you.
Regards,
Oury