Hello there!
You can install the Lansweeper OT hub/sensor on the same server where the original IT Lansweeper is installed. There should be no conflict between the two installations if they use different ports. The default OT installation uses port 85 (HTTPS) for the OT Hub (OT web console), which should not interfere with the existing Lansweeper IT installation.
The OT installation uses port 85 by default, but the installation wizard will warn if this port is already in use.