Is it possible to emulate requests from a messenger using encryption?

Question

Encryption

There is an application for correspondence (for ios and android).
Through special software, as I understand it, you can easily track requests when sending messages.
The application uses encryption. + The software does not have an open API. (messages can only be sent through the installed application).
Is it possible, using only caught (tracked) requests, to learn how to emulate the operation of the application without the application itself. In the case of encryption, that is.
Or is it impossible to do without "reversing" the APK file itself?

Answer 1

Extremely. Few. Probably.