Happy Holidays!
Can OSPW increase the RD capacity or max cog?
It can increase the RD capacity by a bit, like going from a medium to a long cage. It will not increase the max cog that the derailleur will clear. For that you usually need an extended hanger like a Wolf Tooth Roadlunk or similar.
Does anyone know of an ospw that is compatible with sram rival axs? I have one of the KO grabaruk ospws on my gx axs rd and would like something similar for my road bike.