How much would it go against the spirit of SE to allow conlanging flavoured challenges here? Some possibilities (not a complete list) I could see working with the format of SE include:
Reconstruction games. In these, one is given a set of supposed cognates, either as a table or on a map (potentially fictional) and has to try and reconstruct the original word(s). This thread has a bunch of them, each more elaborate than the previous.
Deciphering challenges. Given a short text (sentence or small paragraph) in a conlang and some additional information, either in the form of a direct grammar/lexicon dump or other sentences, figure out a translation for the text.
Construction challenges. Within a limited timespan, construct a conlang sketch and translate a small text (1-2 sentences).
I’m not sure 3) would work well here, but I could definitely see the other two being a fun addition to the site. The question is merely… do we want fun? I do hear that there is a puzzling SE, but the knowledge required to work these challenges might be too specific there.