If it’s complex, you’ll have to dig something up on an internet search.
My advice would be that if your hatch pattern is very simple (just lines) you can create it yourself. It looks super useful… too good to be free… there must be some catch? There’s a website called … but I want to express a caveat that I have never downloaded anything from that site. The attached image shows a couple hatch patterns I made (for Revit actually, hence one for each angle there were ways around that even but I’m risking going off on a tangent here).
Creating a custom hatch definition in an AutoCAD. Chiming in more as an AutoCAD expert here.
