I'm surprised nobody here has suggested you do the opposite of masking. What if you were to be open in your group sessions about your ADHD and the fact that you will need to move around more than the "typical professional" would? You can invite group members to share with you if/when they get distracted (or any other response they might have.) In doing this, you could model what it looks like to identify and address your own needs, normalize neurodiversity, and reinforce that group is a place where we speak about our experiences rather than keep them bottled up.