https://www.roblox.com/Thumbs/Asset.ashx?width=110&height=110&assetId=IDHERE
Also works for other Assets like Models, Catalog items and such
I’m not sure if that’s still working or not
It was working before the Gamepass Update and then it didn’t and then it did and then it didn’t so I have no idea if it does or does not atm
GetProductInfo did seem like it worked at some point I have no idea it was months ago
But the Wiki states
For developer products, this is the asset ID of the product’s icon (or 0 if the product does not have one)
(I would like to know which method works, if you don’t mind replying)