Imma bring back the classics, I and many others advocated for in the old forums.
Me 262 HG-I, prototype flew, aerodynamic cockpit as seen in picture, its forward wing roots were also extended towards the canopy at front as you can see in the last picture. In addition its horizontal stabilizers were modified too.
Overall these modifications improved the aircrafts maneuverability, speed and acceleration, with this aircraft reaching 965 kmh at 6km altitude in level flight.
Suggestion for HG-I which has passed to devs.
Me 262 HG-II, this one is a little more controversial, many claim this never reached prototype phase. But it did, there used to be a good site with all Me 262 work numbers, they listed manufacture dates, locations, and descriptions. It had the HG-II’s work number with it listing it as a manufactured prototype, also couple of books corroborate this.
Fun fact: HG-II was in the official German air tree roadmap in the olden days.
HG-II reached its prototype stage, with at least one being manufactured, it was set to start flight trials but unfortunately allied bombing ended that planes journey.
Originally HG-II was supposed to have a V shaped tail however it was found to not be better than the standard tail so the normal 262 tail was kept for the prototype.
HG-II had completely new wing build, with them being swept at 35 degree angle.
Unfortunately Me 262 HG-III never reached prototype stage.
All Me-262 HG series planes below
Left one is Me 262 HG-I
Middle one is Me 262 HG-III
Right one is Me 262 HG-II