Not going to work in the EU.
Fossil fuels like natural gas are assumed to be the baseline in the Fuel EU directive entering into force in 2025.
All required reductions will have to come on top.
https://transport.ec.europa.eu/transport-modes/maritime/deca...
Looks like another intermediate option is bio-methanol. But, both options are very rare, with diesel being the overwhelming majority of international shipping.
Shifting to either would be a very significant improvement over the status quo. Whether that meets EU requirements is another matter.
https://www.reuters.com/markets/commodities/maersk-buy-bio-m...