In the Yuan Dynasty, calligraphers used headless pens to write seal characters. Unlike other fonts, seal script does not need to consider using side edges or something. It pays attention to using a pen with a leading edge, and it is best to cut off the front of the pen. I tried it, and it worked well. I read about it in books, too.
Big seal script: Oracle Bone Inscriptions, Shi Guwen, inscriptions on bronze, etc.
Xiao Zhuan: Li's divinatory symbols, Taishan stone carvings,,, and so on are all used a lot. You can check them in the bookstore.