How to tell if there is a FlexModule installed on an XG or XGS VIA GUI or CLI

Hello RyanHosiassohn ,

Thank you for reaching out to the community, you can use the ethtool command line. 
Command line like ethtool Port<no> | ethtool -m Port<no> 

Does it say Flexi on it or anything ? 

How would it differentiate between onboard or on fleximobule with the output 

Yes with the "-m" option you'll be able to see the identifier parameter which says the following for example:
Identifier                                : 0x03 (SFP)       
Extended identifier                       : 0x04 (GBIC/SFP defined by 2-wire interface ID)               

Ok thank you so much