Before it's too late - can we talk about Crossups (and Leverlesses with multiple same directions) and them being completely legal in Tekken tournaments?

This solution is pretty much cheating. In case of Crossup this is a simple show case in example of electrics(yt link) & jdcr video about it. Other games quite quickly banned this solution as it was plainly abusing the system, as not a single game was designed with controllers with accessible multiple b,f or d buttons in mind. For that reason leverless users need to use SOCD, but there is nothing like that preventing controllers having multiple of the same directions. With already Knee using it, it's only a matter of time before it becomes a widespread solution, and the later Namco decides to ban it, the more problematic it will be to do so.

The rule change it self is quite easy. "Controllers are prohibited from having more than 1 of the same directional input".