Interior plaster (gypsum cement) sanding: Which grain size to use?

We installed an interior plaster of the type Sakret MIP 02 Fine (grain size 0 – 0.8 mm). The surface is troweled and therefore very rough to the touch (you quickly scrape your finger joints, etc.) and also sands slightly after drying when you brush over it with the flat hand.

Accordingly, according to the painter/site manager, it must be sanded. On the construction site, the painter showed me sanding with a scraper followed by sweeping. The surface turned out well with this method and has already been treated accordingly in the transition area to the fully filled filigree ceiling; but of course, it takes forever with > 1000m³ and causes a lot of dust (the action took about four hours for a 30 cm strip all around on all walls that touch the filigree ceiling).

Now I wanted to borrow a long-neck sander with suitable extraction. I might have a professional device from Flex, now the question is which grit of sanding material would produce a surface similar to scraping and sweeping? In the end, the surface will only be painted twice, no fabric or wallpaper will be applied. The surface should not be completely even and smooth like a baby’s bottom but may still have texture.

Rather coarse (60 grit) at the beginning and finish with 100 grit?

Before I buy sanding materials, I wanted to ask you about your experiences with how you have done this!

Thank you very much

In case someone else ever faces the same question, I’ll answer myself:

Tested today. Result for my plaster: Grit 80 original Flex abrasive fits and produces a similar surface as scraping and sweeping.

and it’s faster and hardly dusty, especially with extraction. But it’s only fun to a limited extent