Is there an "I'm building airport XXXX" list?

Is there somewhere airport devs can search to see if anyone is building or
updating a particular airport for MSFS?

There isn’t at the moment, With the upcoming WorldHub (wu15), the airport that
are being updated with that system will be marked/locked in some way according
to the last SDK q&a; (no more official info about that) You have to take a
look at the forum and discords and Facebook showcases to have a vague idea if
someone is working on an airport A good sign of someone doing some scenery is
the constant presence of the same name in the spot in the multiplayer map
(only if he is connected in MP)

You might find some information [here](
done), can’t vouch for the accuracy or usefulness though…

You can also find this thread on FSDeveloper:

I’m guessing you simply don’t want to waste time on an airport that is already
being developed? If you are confident in your skill level, and feel you can do
a great job, why are you worried about someone else’s version. True it could
limit sales potentially, but if you are better, then you should be OK. Also,
just because someone else claims they are developing an airport, doesn’t mean
it will get finished in a reasonable amount of time (if at all).