There’s no way man...
So you’re going to have a 30A breaker, 10AWG wire. OK so far.
Running to a single outlet that’s rated for 20A. Not OK, wires are too large and outlet is undersized.
Or run it to a 30A outlet and use an adapter to convert to a 20A outlet? OK I guess, but I wouldn’t do it.
And then what? Use a power strip that’s rated for 15A to plug in 30A worth of printers?
No matter what you do here, you have an undersized component somewhere that’s likely to catch fire.
I guess you could use something like this... but I wouldn’t. It’s really not meant for a permanent 24x7 load... (https://www.amazon.com/Conntek-1-5-Feet-Tri-Outlet-Locking-Tri-Female/dp/B007577NLU/ref=mp_s_a_1_6?dchild=1&keywords=30+amp+power+strips&qid=1600387854&sr=8-6)
Pull new wire and do it the right way with 2 20A circuits. If you hack something together and it goes south, you’re on the hook. No insurance is gonna cover you.