I'm one of the current moderators on the Linguistics site.
Our related Conlang proposal has been closed sometime ago and it has now been deleted. Considering this, and the lack of an appropriate place to ask such questions, I've surveyed the Linguistics SE community to see if those questions would be accepted.
Not all users have voted but the most active have done so, and Conlangs are now on topic.
Please keep in mind: this does not mean you just can ask any question. Normal rules apply (NARQ, NC, etc). So make sure your question is not just another "How many Conlangs are there?" which would be quite easy to check online. Narrow down your question, give details, context, don't ask for lists and if you have doubts, consider asking on our Meta site or joining our Chat.