When refining your carbon inventory, your remote team's fuel and electricity use will be estimated in Scope 1 and Scope 2 and you can refine those estimates with real utility data.
Remote work tends to be a very small portion of overall footprints for most brands that make products. You don't need to collect energy use at your remote employee's homes if the associated emissions are non-material to your total footprint.
If your brand is a service or your product is digital, remote work is likely to be a more significant portion of your total footprint and you should aim to collect Scope 1 and 2 data from your remote employees.
You can collect this data from your remote employees by surveying their utility bills and apportioning a percentage of their total home electricity and fuel use to their remote work based on the square footage of their dedicated home office space.