There is not that I'm aware of. I'm not a member of admin. So I can't give you an authoritative response. But I think the answer might be that the Sexual & Gender Issues forum would be an appropriate forum to post in regarding asexuality & aromantics. Here's a link:

https://psychcentralforums.com/sexua...gender-issues/

Plus, of course, I believe you could post in the LGBTQ+ forum on these concerns. That particular forum doesn't seem to attract a lot of activity though. My personal impression is you might get more of a response in the Sexual & Gender Issues forum than in the LGBTQ+ forum. But that's just my personal opinion. I could be wrong. (I often am...)

One thing you can always do is to personal message one of the moderators of a forum you're thinking of posting in to see if your topic would be considered appropriate for that forum. If not, the moderator may be able to recommend a more appropriate forum.