The complete details about the tech system has not yet been released. We do know however, that they will all have the same names as the techs in AA50, as well as the same development method; however, due to some of the changes to the game some of the techs will be slightly different.
The Mechanized Infantry tech will now be Improved Mechanized Infantry since we now have a dedicated mech unit. We don’t know yet what Improved Mechanized Infantry will do; guesses are they can blitz without tanks, they hit on 2 or less, or they hit on 2 or less when paired with a tank (like infantry/artillery). We’ll have to see what they ends up being.
We also do know that the Paratroopers tech will be completely different. It will allow for up to 2 infantry in a territory with an airbase to attack a territory up to 3 spaces away provided that non-paratrooping land units are also attacking that territory.
Also, there is speculation that the Long Range Aircraft tech will only increase range by 1 space rather than 2 due to the addition of airbases. Improved Industries will allow minor ICs to produce 4 units instead of 3 and major ICs to produce 12 instead of 10. Other than that, most of the rest are exactly the same.
Try searching “global tech” or “1940 tech” and see what comes up because there has been a lot of discussion about this so far.