Just a general note and point: Sans mesh inserts and the like, it is not possible to get highly breathable and mosquito proof at the same time. Being mosquito proof necessitates a certain tightness of weave, which will cut down on breathability.
If someone is primarily hiking on trails though, the other option is one I’ve used plenty. Unless the UV is really strong or its cold and windy, I tend to wear shorts, but if there is also mozzies, I just wear baggy mosquito netting oven them or over some truly highly breathable pants (UV). A lot of the pants that people are recommending here would be great for out west (generally lower humidity), but not so good for the southeast imo/e.
Not fashionable I suppose, but works. They don’t weigh much, and they can double as sort of fishnet baselayer in cool and wet conditions when worn underneath another layer (i.e. they put a bit of mostly free air space between your skin and the next layer of fabric).
When I was in Alaska and experienced some truly horrendous mozzie conditions, I was really grateful for the netting I had brought, especially since there was a simultaneous unusual heat wave. (imagine clouds of mosquitoes surrounding you). I would have been miserable in all single layer truly mosquito resistant clothes with the high heat and humidity going on. Instead I had a well worn, long sleeve flax linen shirt with baggy netting top, a wide brimmed hat with head net, and shorts with baggy netting bottoms over.