Hello,
I’m not very familiar with the VP-4, but it looks like there is a dual path mode. This would allow you to put the H90 between the VP-4 Path 1-2.
See page 19 of the manual: https://www.fractalaudio.com/downloads/manuals/VP4/VP4-Owners-Manual.pdf
I’m sorry, but I do not have much further suggestions for how to use the VP-4.
The above setup will be mono, so you’ll need to do something else if you’d like to use your pedals in stereo.