Hello everyone, thanks for all the ideas 😁
It's not a vintage watch, but it's around 10 years old, the strap is original leather.
My watch winder has this plastic like smell, so after the watch stayed in there for a few days(to test the accuracy), now it smells like that. Yesterday I did however use a wet wipe without alcohol or perfume and then I used a damp towel and then paper to dry it. So now, I can't smell anything. Just to elaborate, there was no visible dirt or anything and the wet wipe didn't get dirty after wiping it. I believe the seller had already cleaned it, but then stored in a basement or something. 😁
On the box, I used mold removing liquid, a strong one, so there's no visible mold or anything, but it still smells if you bring your nose near it. It's that basement smell. I will try leaving it out in the sun for a few hours soon.
On the topic of straps - what's your goto place for high quality learher ones?