Every bank is now attempting to get into the private blockchains among the other banks and trying to use the ledgers for their internal work. And also making sure to settlement goes right and they can do the banking lot more accurate and easy to verify. 

Deutsche Bank is in motion to work on the L2 of Ethereum using the ZKSync and they would be using this for the banking and the ledger. 

The move to the public and private blockchain does have some of the consequences which people have to adjust to and go through. So it would not be something that easy for the banks to adjust with. They have to deal with govt, compliance and the people with the reports going against blockchain too. 

For example what to do public and what to do with the private and how to keep the records on the chain. That is what most of the EU based banks are struggling ads they are getting a lot of heat from the people around. And also the compliances make people do more public content with their transactions on blockchain. 

So Memento and the bank coming together for the layer 2 solution would be something to watch around. And if things work around properly this would make life a lot easier for the banks and also for the services around. You can check out the memento homepage to learn more.