You could create a new Calling Party Transformation to strip the +1. This will only affect the phone screen during ringing, the missed call log will not be affected so users could still get the +1 on the numbers there.
To create a CPT, create a new partition and CSS like normal, go to Call Routing/Transformation/Transformation Pattern/ Calling Party Transformation Pattern and add a pattern you want to match like \+1.XXXXXXXXXX and discard pre-dot. Then assign the CPT CSS to the phones' device page under Remote Number/Calling Party Transformation CSS and uncheck Use Device Pool CPT CSS.