Mostly just thinking whatever it would take to make it an 1100.
The bore is the same, the stroke is longer on the Africa Twin.
The 1000 AF and the Talon share the connecting rod, piston pin (but not the piston), clip and rod bearings. They do not share main bearings but the Talon and Pioneer share main bearings.
What you are asking would entail somehow putting the AT crank in the Talon and it doesn't look possible. The AT has 2 balance shafts and 2 balance shaft gears but the Talon only has 1, making the front of the crank shorter. The rear of the Talon shaft looks longer and has what appear to be much finer splines.
2021 AT parts are not listed yet so it is hard to tell if they changed the piston, rod or block to accommodate the additional stroke. If they changed the rods then the easiest way to add the 85 cc's would be to have the Talon crank stroked and swap rods to the 1100 AT rods.
Personally, (aside from the turbo) I think proper head/cam/piston work and a good tune to go with it will be the most cost effective as soon as that type of mod is perfected.