Create a metric based on two metrics from differents models

Hello!

Is it possible to create a metric based on two metrics from differents models?
I have a metric ARR (SQL based) and an other one Subscriptions (that is the number of customers).
I want to divide ARR by Subscriptions to have the "average basket".

However, if I start a question from ARR metric, then the other metric isn't shown. And vice versa.


And I cannot join both because they are not from the same source in metabase?
Can't find how to simply use two different metric and divide them to have a new metric...

Thanks in advance for your help!