The big difference is that sows come into season about every two weeks, which is the main reason for any grumpiness; not every season is noticeable though. You may find the sow behaviour sticky thread at the top of this section helpful.
Sows are wired to live in hierarchical small groups, whereas with boars you always have a latent rivalry to fight for a place - and the right to father the next generation - with a sow group (which is the reason why boars should not be kept within line of sight and sniff of pheromones of sows).
Fall outs and fights amongst sows are therefore rare, once a new member has been accepted right at the beginning. That doesn't necessarily mean that every sow bonding runs smoothly, though, or that all sows are always happy to live together - especially not, if you get two dominant girls!
Generally, there seem to be more laid back boars than sows.
There are no dietary differences, unless you are dealing with a pregnant sow.
If at all possible, please consider rehoming an already bonded pair from one of our recommended rescues and help making space for yet more piggies in urgent need of experienced care.