How to give Subtask creation access to Project Members

Hello

That's not going to be possible. The rights you distribute cannot be implemented. The elements for which they are responsible and their own elements cannot be applied to creation rights. If they can create sub-activities, then they must be able to create activities.

Perhaps the best option would be to give them access to the todo list , which would allow them to break down an activity into sub-tasks to be completed. They can be tracked with flags such as in progress, done, and closed, a manager, and which offers a dedicated screen in addition to a section on the activities screen.