Specs wise, this should work as long as you switch the outlet to 12V. According to the manual, using a current doubler cable should give you 500mA (12V 250+250). I know the H90 has a startup spike of around 565mA. I don’t know whether the Pedal Power 2 Plus has the capability of reinforcing current where it’s needed for this spike like other manufacturers. May want to ask their support. This is the reason Eventide recommends 12V 600mA.