Is there any easy, documented or official way to replace pullback mechanism with Motor Set 8293
I dont't see how a standard way could exist. That would pretty much require a setup with a PF motor, gears, etc. having the same size and interface as the pullback 
motor, which according to bricklink (I don't think I have any) is 6x5x3. As far as I remember the only PF motor shorter than 6 studs (there has to be room for at least one gear) is the XL, but that's 5 studs wide.

For any given set, it's quite possible that you could find a solution, and even that the same solution would work for a lot of sets.