Hi Dylan, yes sir, this will accept 18rd magazines as well. Make sure to get magazines specifically made for the compact model.
Do not use the full size mags on the PDP Compact or you may damage your pistols ejector.
The magazine you want is currently out of stock at Bud's budsgunshop.com/product_info.php/products_id/153382/walther+arms+2855364+pdp+compact+18rd+9mm+black+aluminum ,
Stay safe & have a great day!

yes it can. the 10 round is just a modified 18 round magazine to be legal in mag restricted states

Hi Dylan and welcome. Yes Sir it can without issue. Most manufacturers including Walther make 10rd magazine packages so their firearms can be sold in States with magazine capacity restrictions. The only difference is the magazine (10rd) compared to the standard model package 18rd magazines. The firearm will accept either capacity magazine. Cheers, stay safe and enjoy!