MT3608/SX1308/... boost converter shutdown current (module)
Not sure if you still care, but...
I think you'll find that the schematic for those modules is shown here: https://www.youtube.com/watch?v=zJJcdptSH80&amp;t=151s
The datasheet states the FB pin leakage is 1-50nA, so you should be able to reduce the current through your resistor divider to e.g. 1uA.
It's possible that the MLCC are leaky; you can desolder them to check if they are increasing Iq during shutdown.