Please, is it possible to deploy our extension (.app file) to our customer’s production environment without passing by AppSource (submitting validations)?
In other words, if it is possible, how does Microsoft validate the .app file before it is installed on a customer production environment?
Thanks in advance for your answers.
Assume that you talk about Dynamics 365 Business Central? If that's the case, then yes. You are able to have custom Extensions in the 50000-99999 object number range, created in a sandbox, installed in your production environment. It doesn't have to go via AppSource.
I have moved your question from the generic D365 forum into the D365 Business Central developer forum.