All three of the '109's in the video are owned/operated by Hangar10/Air Fighter Academy, located in Germany on the Island of Usedom. The DB605 powered Bf-109G-6 D-FMGS is a new-build airframe using original parts/identity. The DB605 powered Bf-109G-14 D-FMGV is a converted Buchon though registered with an original G-14 identity. The two-seat Buchon, D-FMGZ, was restored to Bf-109G-12 configuration (and registered with an original G-12 identity). As mentioned, they can swap in/out either an original Messerschmitt QEC with DB605 engine or a Buchon Merlin QEC, on the "G-12/two-seat Buchon" - however, ever since they put the Merlin back on it, that is the only way it has remained (I have a sneaking suspicion that the DB605 it originally had when first completed is the one that is now installed in their recently completed "G-14" D-FMGV).
The T-6 was leading the formation as it was serving as the photo ship for that photo flight (cameraman in the back seat).
I don't recognize the pilot wearing glasses, but the two other pilots are Klaus Plaza (world-renown German warbird pilot and test pilot) and Mark Murphy (highly experienced American warbird pilot, who owns/operates the P-51D Mustang "Never Miss" and regularly flies an FG-1D and the Mk.1 Spitfire P9374 for another owner). As I mentioned, I don't immediately recognize the pilot wearing glasses, but he is far from the first warbird pilot I've seen wearing glass - in fact there are quite a number of notable warbird pilots that do, not to mention perhaps the world's most highly respected and well known warbird pilot of all, Steve Hinton.