Mendix cloud provides you with one data instance and one file server s3 instance per node . That means all the data will be stored in a single database instance.
Now coming to your question , can you have multiple domain model --» Answer is Yes , you can do that by adding a New Module .
For your second question Its not possible as per my knowledge .
Hope this helps.
If i get it correctly you want client data in its own app app lets say the consumer app data in different app if that is the case u can build these two different apps with relevent data on each side and build an integration through mendix datahub or rest services[expose the required entities and consume then on other side]
Every module in mendix have its own domain model where you can create the domain model of the app based on your requirements related to particular module in same way you can achieve your requirements.
Consider building a multi-tenant application:
and an example using this module is here:
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