Create Databases over cross Stacks

Howdy Folks,

I actually working on a shared hosting enviroment for evaluation.
I have an stack for the galera cluster that working very well, and an shared dynamic LB that I can make the DNS working with labels.

So, I want to create an stack for each customer with an Application Container and fully configured instance, so my question is:

How I can create an new Database + User in the Questions Dialog of an Catalog Item in an additional Stack (Galera Cluster)? Any known ways or is anything like ansible needed here?