This probably isn't new, but I haven't seen anyone do this desync before, even though I have seen people do it OOS. If Nana is in end lag of a move, she is unavailable to join Popo for synced side + b. This has the same effect as Nana being in shield while Popo has just jumped in the OOS version. So while Nana is in end lag and Popo is not, side + b desyncs.
The easiest way to do this is input an attack and then mash side + b. It even works with jab. You could time it so the side + b input is right when Popo end lag is over but Nana is still in lag, but there's no downside to mashing other than Popo leaves the ground a tiny bit.
Assuming this isn't new, why don't people do this? It seems like a great mixup, it's easy to do, and can be done pretty much whenever. With a follow up Nana blizzard, I'm guessing it's not that easy to punish.
The easiest way to do this is input an attack and then mash side + b. It even works with jab. You could time it so the side + b input is right when Popo end lag is over but Nana is still in lag, but there's no downside to mashing other than Popo leaves the ground a tiny bit.
Assuming this isn't new, why don't people do this? It seems like a great mixup, it's easy to do, and can be done pretty much whenever. With a follow up Nana blizzard, I'm guessing it's not that easy to punish.