Several conditions were required to use Dante's sword strike and gun moves in the real world. First, the users' bodies had to be strong enough to withstand two conflicting and alternating forces. Second, these people had to have powerful physical strengths and granular control. Lastly, they had to have insane sword attack speed and gun-drawing speed.
Besides, they need to have a handgun which could fire quickly and provide a great and stable recoil force.
Only when all these conditions were met could one achieve Dante's stroke-like attack speed and launch heavy strikes while remaining in the air.
In theory, it could be achieved.
Of course, it was only in theory. After all, many people couldn't even do it in the game, let alone in the real world.
Anyway, no one could master a technique in one try.