Because the local “conservative” homeschoolers groups were all tied to membership in specific churches/evangelical fellowships, we belonged to a “liberal” homeschoolers’ support group for almost 10 years: pagans, seculars, left-libertarians and the occasional Democrat.
It was a worthwhile group. They didn’t hassle us for being Catholic and even bringing religious themes into the projects we shared. For the most part. (I had to convince one pagan mom that if it was OK for her kid to picture Gaia, it was OK for mine to do Noah.)
Liberal homeschoolers are OK. Like us, they’ve probably more independent-minded than most other members of the herd.
We met quite a lot of liberal homeschoolers doing science competition, especially the Envirothon. As long as their child memorizes the soil levels correctly or can calculate the movement of glaciers, I don’t care if they worship Gaia or nobody.
We never joined the big homeschooler group in the area, because I was never sure, as Catholics, that we'd be completely welcome. We had a small group, and we were the only religious folks in it. We never did 'Catholic' homeschool, anyway. We didn't start homeschooling until it was just the two younger kids, and they were both in Middle School at the time. We went thru high school, and they did college prep high school, with religious instruction for Confirmation making up the religion part, because it spanned almost three years.