In general it would depend on how exactly the App in question does it.
/e/OS includes microG, an Open Source replacement for a number of crucial Google services, enabling many Google-dependent Apps to run on degoogled phones.
In case of JazzCash somebody would simply need to try it out in practice, like users do to assemble the list over here … [LIST] Banking Apps on /e/OS.
But as @aibd found on the website already, JazzCash doesn’t even need a smartphone, so it seems there would be a way to use it in any case.