All good advice above.
The math is relatively simple. You can work in watts, or you can work in amps.
The A/C's may each draw 13 amps while the compressors are running.
13 + 13 = 26 amps.
However, when a compressor starts it may draw twice that. Most AC circuit breakers allow for that. Starting two at once will likely trip the breaker.
A microwave can also draw 13 amps or so. They generally don't spike such a high starting load.
13 + 13 + 13 = 39 amps. The circuit breaker will trip.
An electric water heater will draw 13 amps when the thermostat switches "on".
A big battery charger can draw significant AC current. However, you cannot just add the 12 volt charging current to the total. A 100 amp battery charger may draw 11 amps at 120 volts AC. A 50 amp charger may draw 6 amps at 120 volts AC.
When batteries are fully charged, the battery charger will draw very little AC current.
So turn on no more than two high current items at a time. Start one A/C and wait 5 minutes before starting the second one. If batteries are low, charge them for 4 hours or more before starting the second A/C.
The worst that can happen is the pedestal circuit breaker will trip. Then turn things "off" and reset the breaker.
Note: A few campgrounds have circuit breakers located in a central panel. It can be inconvenient to get a service person to reset the breaker.
I wish you good luck and happy trails ahead!