Taotree Journal Planner Pens, 24 Black Fine Point Pens, Ideal for Art, Crafts, Scrapbooks, School, Office, and More

Could it be this type of fiber tip fineliner? There are plenty of generic brands on Amazon: https://www.amazon.com/Journal-Taotree-Fineliner-Journaling-Supplies/dp/B07VRJXP65?th=1