One solution I’ve seen is to allow customer to choose the cloud and region so the managed service is as close as possible to the customer’s existing infrastructure.
Logz.io comes to mind: https://docs.logz.io/user-guide/accounts/account-region.html. I’m sure I’ve seen configuration for other services, but haven’t cared as much since usage was sufficiently low and latency-insensitive that the region didn’t matter.