No, there is no way to do such a thing without use values higher than 0 for layerno.
However judging the lifebar design from the screenshots, you could use the upper bars for the 3rd and 4nd players, and the lower ones for 1st and 2nd players. So you can reverse the values of the portraits, using p1 values for the p3 and vice versa. The same goes to p2 and p4.
Dragon Ball Super is about: Lazy plot, kawai eyes, incoherent levels of power and deus-ex machina (all the time).