Pro Tools is restricted to using only AVID’s proprietary RTAS or AAX format plug-ins. Currently, Equator2 and ROLI Studio are only provided as AU and VST plug-ins for maximum compatibility with the majority of DAWs. We are unlikely to be making new AAX plugins anytime soon, so until Pro Tools opens out their plugin format compatibility, ROLI plugins won't be compatible with Pro Tools.
Here is a guide on using other instrument plug-ins – like Cypher2 and Strobe2 – in Pro Tools with the Seaboard.