These two are not really substitutes — they are different financial products wearing the same card shape. RedotPay is a spend-your-own-balance crypto card with wide global coverage.
The Nexo Card can run in credit mode, meaning you borrow against crypto collateral instead of spending it. That is powerful if you do not want to sell, but it introduces liquidation risk a prepaid card simply does not have. Nexo’s availability is concentrated in the EEA and a set of supported regions; RedotPay reaches much further into emerging markets.
Outside Europe, RedotPay is usually the one that actually onboards you. In the EEA and want to spend without selling your crypto? Nexo’s credit model is the reason to look. Fees we have not personally verified are labelled unconfirmed.