Managing presence indicators such as Available, Busy, or Away to reflect user availability
Here’s a good work around:
Go to the calendar page and click the “Meet Now” button without audio and no other participants join now. Your status is updated to “In a Call” Then tab over to my profile and set your status to “Available” instead. As long as you are in your "imaginary" call your computer won’t idle and Teams won’t change your status and your status will be Available until you leave the "Imaginary" meeting.
I tested this and it works perfectly!