nothing special of R10 Ryzen socket.  It is the same AM4 socket for zen, zen+, and zen2 Ryzen.

wiki: The AM4 socket specifies the 4 holes for fastening the heatsink to the motherboard to be placed in the corners of a rectangle with a lateral length of 54×90 mm.

any pics ?

I realized there is a significant physical limitation of air cooler height due to the swing arm psu.  you will have to get a very low profile AM4 heatsink.

look at back side of R10 and clam shell swing arm psu.  R10 closed    R10 open 

your air cooler can not be taller than the blue arrow in 1st pic.  You can get a ruler to measure it.  my crude estimate is less than 2x width of IO shield (44 mm). so blue arrow is about 80 mm. 
well, The NH-L9a-AM4 cooler with fan is 37 mm tall.  it should fit.

R9/10 have same case.  here is a pic of intel 1151 air cooler in R9. R9 

Hi I got an r10 with stock air cooler, the screw holes are mounted in square just like the intel ones, not the AM4 90/54 spacing

R10 w Ryzen but Intel air cooler, is that possible?  Is it R9?

I have stock pic and DP/N of Dell AM4 air cooler low profile 95W which would probably fit R10.

@Anonymous @redxps630 somehow my last reply was detected as spam..here's the pic for my r10 3700x, the holes spacing are square. I had bad experience with liquid cooling, so i would rather go safe with air cooler, never thought the performance is so bad. cpu temp reaches 95C running my own simulation, 80+ for games. I'm considering get some super low profile air coolers.

Aaannndd once again, their documentation is outdated on the support page.

What is surprising to me is no VRM heatsinks at all on that board.  Whereas with intel 8400 or 8400 and air cooling you get 1 vrm heatsink.

And with higher ryzen cpus you get 2 vrm heatsinks.

I meant to say 8400 or 9400, but can't edit my post due to the AI spam bot.

@r72019 :

Maybe Dell thinks the VRMs won't be pulling high current. The PSU power cables look like they are from the 460W and not the 850W unit.