I have a set of PowerShell scripts that include a \"common\" script, located in the same folder, like this:
# some-script.ps1
$scriptDir = Split-Path -Parent
alternatively rather than using filepath.. you could pass in a scriptblock, that dotsources the script from a UNC path that all machines have access to. However each machine will need to have the appropriate executionpolicy set so that they can run that script from the UNC path
let me be clear though, that i'm not saying to run the script from the UNC path as if that does the remoting, but still using invoke-command or start-job to run a scriptblock on a remote computer. It just happens that that scriptblock will run the script from a UNC path for convenience.