Tales and Chronicles
Jewel of the North, formerly know as vincegetorix
In this case the Dmguild is your best chance. Sort the result for PWYW adventures and pick a theme that inspires you.
I think it'd be hard for any new DM to run any adventure that's more than 2-3 pgs in one session. There was a good series in AD&D (1E & 2E) called Book of Lairs. They had very short 1-2 pg scenarios that I feel could very easily be converted to 5E easily as they all mostly center around a single monsters or group of a single monster. This provided they are in the MM, some monsters were setting specific.I love LMoP, but it's not a one-shot.