OmniScope can read ACES color science input which means that the OpenFX plugin can be applied directly in the ACES timeline in Resolve with no other conversion plugins.
To make it work just select the ACES version in Options / Preferences window:
ACES mode selection
You can also specify the ODT for the ACES transform in which OmniScope will monitor the signal:
- Rec. 709
- Rec. 2020
- Rec. 2020 ST2084 1000nits