I usually do it 1 of 2 ways....
• Using a very hard and sharp center punch, punch a divot off to the side of the head, then chase that around in a counter-clockwise direction with taps from a small hammer. The screw usually loosens within a quarter turn.
• If the screw is soft enough to wallow out, then it is also soft enough to drill. Measure the dia of the screw thread, and choose a sharp drill bit ever so slightly larger. Place the drill bit into the wallowed out Torx pocket and start drilling straight in. The screw head will fall off soon, which releases the grip. When the grip is removed, the shank will be standing proud where it can be removed with pliers.