If everything is wired and operating correctly you shouldn't have a problem.
The XM1800 control panels even identifies when the inverter is in pass through mode (green light) or running off the batteries (yellow light). Not sure which inverter you are getting but the Xantrex (power on) will run on pass through until shore or generator power falls below 90 VAC and then switch over to battery power.
US Army (Ret)
2020 Entegra Accolade 37TS
2019 Jeep Grand Cherokee Trailhawk (Toad)
FMCA - F432054