Can i create a cross-region read-write replica with Amazon RDS?

I am in the process of setting up two VPCs in America and Europe. Both will contain a database that needs to continuously synchronize with the other.

I know that one can create a read-replica from an existing RDS database that can also be cross region. But this replica also needs to handle write queries. I've read that such a replica can easily be turned into a regular database by turning off the read-only option. But if i do that, will the database still synchronize with the master database it was replicated from? And will the master database update when i write something to the replicated database?

I know that there are better options for creating such a setup, like Amazon aurora Multi-master. But the problem with aurora multi-master is that it does not work cross region. There is also aurora global database, but that basically works with one read-write master instance and multiple read-only instances as well.

I need all my cross-region instances to be both synchronized and writable. Can i achieve this using only Amazon RDS?

Thank you