Hello, this is the problem: I have a "material" resource assigned to 100% for a task A, and a "work" resource assigned to 0% to perform the task A, and at the same time assigned to 100% for the task B.
My wish is visualize in the "Team Planner" view that "work" resource will be occupied for both the tasks

Material resources as set out by Project do not have assignment units. You can change the type of the material resource to Material - but it sounds like your "material" resource is a work resource.

Work resources perform work - not material resources. It sounds like you have things backwards. If Resource A is performing the task, they cannot be assigned at 0%.

Please tell me why you are doing what you are doing. I understand you wish to see that the work resource is assigned to both tasks in team planner - but with zero assignment units, that is not going to happen. The Team Planner view shows you work resources who are assigned to tasks and have a work value.