you can add a separate circuit aka (break it out) for the a/c and use a separate 20amp shore cord for it
keep the Rv and converter on the OEM shore cord
there will be times when you want that converter power charging batteries and powering the MW
mother nature doesn't always give you all the sunny weather needed for battery charging from solar
and i can guarantee that the A/C uses a lot more power than top off battery charging
IF its sunny and hot and you want A/C the tiny bit added by charging use will be miniscule compared to the charges for running the a/c
and since the converter works at night off shore power..you will be able give your batteries a rest and let them top up to full SG
BTW i don't normally camp where the a/c is metered so when i pay to camp, i want to get my batteries charge and get out my portable charges and put them on equalize
we full time mostly off grid dry camp 505w solar, residential fridge, generator etc.
believe me..when you pay to camp , you want to maximize your battery charging not just use the A/C..i heat with propane..but i cook with the MW
i know about power use
break out the a/c circuit IF you want to
but don't rob Peter to Pay Paul
when you have shore power, use it to desulfate, equalize, revitalize those batteries..DON'T short change your self over the few cents , of electric for the batteries, and thats only where there is long term parking with metered sites
any over night or weekend you will be charge a flat rate for the campsite, no matter how little or how much power you are using
now if you spend the winter in Quartzite or RGV Texas at one of the places that offer seasonal parking with metered electric
then you might save a little, by charging off solar during the day and powering lights and TV at night, but then you won't need the A/C in the winter, and electric heat costs as much or more as A/C
but yeah maybe you could reduce the electric bill
but you can do the same thing by turning off the main breaker in your panel and only using the electric when using the A/C or MW or Coffee pot, and not have to worry about the re-wire