Click here for a blog post that describes how to move a PDB database from one container (on-premise) ton another container in Oracle cloud. This procedure can also be applied to on-premise to on-premise, Cloud A to Cloud B, or on-premise to any Cloud, as long as you have access to the Operating System and can move the pluggable database files.
Note that Oracle is a bit picky about making sure that versions and character sets match when you perform this unplug/plug process.
We haven't tested unplugging/plugging of databases to/from all these different cloud platforms but they are basically all just normal Oracle databases on different provider's servers.
