I have NO experience with how the dropper bottles do when taken on a plane, BUT... I have a thought!
Do you have any of the screw-on caps for the tincture bottles? I think that they would be safer than the 'dropper'. I think the dropper may leak. I have purchased dropper bottles that have the dropper AND the screw-on cap. I would take the safety step of putting any liquid in a leak-proof container. You just never know and I would hate for you to open your suitcase and have tincture leaked on everything.
As for tinctures in a carry-on raising an eyebrow... you just never know. I think every airport and airport worker have their own 'take' on little brown dropper bottles.. LOL! You could call the airline and ask about regulations or read online about WHAT and HOW things can be carried onto the plane.