Yes. Connect the 2 sends from the Helix to H90 inputs 1-2. Connect H90 outputs 1-2 to the 2 returns on the Helix.
Set the H90 input/output level for 1-2 to line level. https://cdn.eventideaudio.com/manuals/h90/1.7.1/content/system-menu/io.html
You should be all set.
