How do I report these? For instance, I have a case where I invested some ETH into a presale, in exchange for the token, but instead of launching trading for the token on uniswap, they stole the eth and disappeared. Do I send these coins to a burn address, or can I mark them somehow to get a tax deduction? Thanks.
I believe that the “Lost” tag is for this sort of situation. From the Koinly help centre:
The Gift/Lost/Donation labels are special and will result in the withdrawal not generating any gains. It is as if you sold the coins for the same price that you bought them for. You should only use these tags if you know that your country does not tax Gifts/Donations/Lost assets.