At first this is going to sound totally 100% bonkers but hear me out as it does usually work.
A car-detailing trick from back in the day to de-emphasize a very small, light surface scratch without using touch-up paint:
Take your index finger and draw it across your forehead from one side to the other while applying a bit of pressure.
Then take that finger and go over the scratch and the inherent oils from your forehead skin will fill in the scratch and darken it.
Any excess oil outside of the scratch (your matte finish color will highlight the excess oil outside of the scratch)
can be wiped away with either a dry Q-tip or cotton cloth.
This trick works best on medium to dark colors and will last for quite a bit.
Give it a shot....