Generally speaking, simple surgical treatment will leave traces. If it is surgery combined with non-surgery (laser), or part of non-surgical treatment, it will not leave scars. For example, laser birthmark removal is an ideal way to remove birthmarks.
Laser removal of birthmarks is very effective, but laser can only remove a part of the pigment at a time, because the damaged pigment is three-dimensionally distributed in the skin. To achieve the desired effect, it usually takes 3-5 times of treatment, and the interval between treatments needs more than 3 months. This is because the swallowing and removal of broken pigments by the body is a slow biological process, which generally takes 1~3 months. If you don't consider the endurance of the skin, if you want to remove the birthmark at one time, it is likely to leave a scar. Don't worry about leaving a scar.
In fact, you don't have to worry about scars, because lasers also have the ability to remove scars. If there is a scar after mole removal, you can use a laser to remove the scar. Of course, this requires that the scar is not very serious.