Hello,

The Ox Box should not be used as an insert as it needs to connect directly to your amp.

I would suggest using Dual Mode on the H90 and trying this:

Guitar > Compressor / Drive pedals > H90 Input 1

H90 Output 1 > Guitar amp input (amp connected to Ox Box)

Ox Box Outputs 1-2 > H90 Inputs 3-4

H90 Output 3-4 > Stereo monitors

This setup will allow you to have different effects before/after the preamp stage. Press the routing button to choose which preset is on which path: https://cdn.eventideaudio.com/manuals/h90/1.8.6/content/edit-modes/routing.html#dual-routing

Let me know if you have any questions.