Apple Pencil 2 leaving marks on my iPad screen

You should ensure that your iPad screen and the Pencil tip are kept clean - and free from dust or other particulate material.

Dust and dirt can contain hard abrasive material. Basic material science tells us that a hard material can become embedded in a softer material - such as the replaceable Pencil tip. When the Pencil is dragged across the screen, the embedded hard material can leave marks or scratches on the glass screen of your iPad.

You may find that using a good quality screen protector will avoid damage to the iPad screen. A screen protector provides a sacrificial protective layer that can, it becomes damaged, be easily and cheaply replaced - unlike the iPad screen which is the single most costly component of the iPad that cannot be easily or cheaply replaced.

As far as traces.....It depends on what your meaning of traces is. If you're talking like marks that wipe off when you wipe off the screen, that's not abnormal, I mean you are placing something on the screen and moving it around so it's going to possibly make marks in the oils and things that might be on the screen from you touching it as well.

If it's leaving scratches....That's not normal and I would make sure that you don't have any dirt on the end of your pencil before you're using it on the screen of your iPad. Also make sure that the tip isn't worn out as the coating of the tip can wear out over use and if the tip isn't replaced, the plastic can scratch the screen.