Custom Highlight of Vertices in Edit Mode

Hi, im trying to write a script to make custom highlight with glow effect for vertices/edges just like a “mark seam” function but without any actual effect only just visual
image

Im modder and im decoding data of model, each vertex have an indexies of locator data it’s defines which vertex will move according to animation

and i will write script which would visual show me this data and i want to make it in reverse i will “paint” vertices and somehow script will get the data of them and translate it to hex

but idk how to “paint” vertices by code and get the data to code

PS Im sorry for my bad english it’s my second language