It is possible to edit a utility meter set up within the GUI, *BUT it is not for the faint hearted.
If in File Editor or VSC Code you go to:
\YourHA_ipaddress\config.storage\core.config_entries
you will find a file with all the data. That is a double \ at the start of the address - this formatting knocks off the first backstroke.
A recent update to HA made this harder to decipher but you will find each entry starts with a new number in VSC Code.
For example, this is a GUI Utility Meter to measure energy use by my coffee machine:
{"created_at":"1970-01-01T00:00:00+00:00","data":{},"disabled_by":null,"discovery_keys":{},"domain":"utility_meter","entry_id":"bb0b23e1c2db91e9be4c8dbca982278","minor_version":2,"modified_at":"2025-08-07T01:55:26.985603+00:00","options":{"always_available":false,"cycle":"weekly","delta_values":false,"name":"Coffee MAchine A Weekly Energy","net_consumption":false,"offset":0.0,"periodically_resetting":true,"source":"sensor.coffee_machine_energy","tariffs":[]},"pref_disable_new_entities":false,"pref_disable_polling":false,"source":"user","subentries":[],"title":"Coffee Machine Weekly Energy","unique_id":null,"version":2},
Use with caution - and maybe set up a test meter first.