Can you add sport auto trans to existing car?

I have read that the faster shift times, i.e. the only real benefit to the sport auto trans, is just firmware. If I don't care about the paddle shifters, is it possible to just add this feature to an existing vehicle. I know it sounds very far fetched and dumb, so no harassment, I am just wondering. I have found a new 335xi that meets every single requirement of mine except sport auto trans and it would be the best new ever to know I could have it.