I am pretty experienced with Little Nightmares, and I would like to know the requirements for a mod/verifier since I enjoy watching all kinds of Little Nightmares speedruns and am willing to grind for this title.

There is no list of requirements for mods/verifiers. It's mostly do we need additional verifiers and do we believe the person in question is suitable for the team. Considering your profile is just one week old and you haven't run anything yet the only thing I would suggest is running a few things and gathering experience in communities and if we have demand for new Mods/Verifiers I'll come back to you if we (as a team and community) feel you would be a good addition^^ GL and Happy running