Yes, you can play Bright Island through The Second Encounter.
If your The Second Encounter installation is in Steam, it should detect every other game and mount them automatically.
If it’s outside of Steam (or under a different Steam library folder), navigate to Options -> Classics Patch -> Config properties and setup paths to Revolution and its workshop. Or change them directly in the configuration file (SSRDir and SSRWorkshop properties).
If you setup Revolution path but leave workshop path empty, it will automatically detect it relative to Revolution path.