Task Assignment between two application

That's simple. Just assign the task to that group. There is no wall between applications, other than security settings.

I would create a group in App A and assign the task to that new group. Then make the group from App B a member of that new group. This way, you have clear a assignment approach inside App A, but can still include users or groups from the other app.

That's simple. Just assign the task to that group. There is no wall between applications, other than security settings.

I would create a group in App A and assign the task to that new group. Then make the group from App B a member of that new group. This way, you have clear a assignment approach inside App A, but can still include users or groups from the other app.

In Application A, once a user from Group A completes the task then that flow gets completed.

Tasks to Group A and Group B are not in the same flow.

For Group B there is an another process model which is in Application B.

I need to pass the task details from Application A to Application B so as to assign it to the Group B.

This is confusing ....

Did you try to just start the process in B from the process in A?

Ok, I'll try that.

you can use the start process smart service or subprocess
in the subprocess, you can call the application B Process model

You'll have to be careful here not to create a circular dependency. If Application A calls a process in Application B and then Application B calls a process in Application A you'll have problems deploying those Applications to higher environments because each will have a dependency on the other.

One way around this is to decouple the two and have them call each other via WebAPIs which are only resolved at run-time. So Application A will call a WebAPI exposed by Application B and that WebAPI can start the relevant process to create the required Task. And if you need to do the reverse then again use a WebAPI to do this.