When it comes to referring cryptocurrency, you could easily get into legal trouble if that cryptocurrency turns out to lead somebody to financial ruin. This is because you gave them bad financial/investment advice and that person could decide to lawyer up against you for that
Many self pro claimed financial advisors always mention it's not financial advice in the bottom of their sites or they mention it in the beginning/end of the videos. Honestly I don't really know how the law works, but it seems most of them can get away by just saying not financial advice even though they're the brand ambassador or convincing people to buy those coins.