abs slurry is primaraly used as a print adhesive for abs prints.

I suppose if you made it thick you can use it as a sort of 3d paint.
But breathing acetone is not recommended and while your are recycling the abs, you are also releasing a lot of acetone into the atmospehre.
It's also an extremely volatile and flammabe vapour and liquid.

So not sure how 'green' it is.

The best advice is to just try and not print things - like benchies - that are just waste plastic from the get go.

When you see what is involved in making decent printer filament - it's not going to be a home industry any time soon.

Until we get a reliable hopper fed extruder that will take bulk plastic pellets - and consequently recycled plastic pellets.
Home recycling is just not viable.