Font Forge Script help

I am trying to modify a font (not a roman script, the glyphs are ideograms)

I'm new to FontForge and I struggle to do operations like the following. I suppose that the only possible way is to use a script. Say I have a glyph selection, I'd like to know, for each glyph, what is the lowest point (Y coordinate), and to move the glyph according to a delta I give. Here's a specific example:

Is there way to achieve this? Command line, script, etc.

I searched Stackoverflow for hours. I didn't find anything related." (I also obviously looked at the FF documentation)

 

Any help greatly appreciated!

Thanks in advance...