So I impluse-shopped and bought a 3D printing pen off Qoo10 today. Did the order at work during the lunch hour and dropped by the seller’s shop to pick up the item after work.
My pen is some OEM pen. No branding. The instruction booklet comes in English. so no issues there for me. The pen runs off USB power and comes with its own USB power cord, so I plugged it into my power bank and it worked.