You can. Be very careful though! If you're doing this with a character like Guts, who has a sort of tint to his skin and a subtle black wash, it can result in the acne area being lighter than the original skin tone. I think if it's a light skinned character with no paint applied, it's safer. The front of Guts is fine, but the skin became lighter in a couple of areas of his neck because it faded the wash. It didn't do this everywhere though. The acne cream also faded away the bottom right of his brand, so I do NOT recommend applying to any figures that have surface decals ( I did very carefully apply with a tooth pick to avoid the actual brand and tried to just get the dyed parts, but it still faded a little regardless) I have a custom head ordered, which is why I took the risk experimenting with the stock head and wasn't too annoyed about things fading.
I applied a little cream to each area every morning, then wiped it away in the evening and applied more at night. Did that for about three weeks.
Guts was particularly bad because he had cape damage, plus black scuffing from falling from the shelf due to loose joints. He was one of my first 1/6 and I didn't know anything about dye transferring to figures or the need to wash capes, so I had his collar up high, touching his face for a long time.
https://www.amazon.com/gp/product/B00NR1YVYU/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&psc=1
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