Bitcoin
cli – How to run multiple samples on Windows bitcoin-qt
How to run multisample bitcoin-qt for one block data directory using different wallets?
It is not expected that two instances of bitcoin-qt can be run simultaneously using the same block data directory.
This is because they are both updating the same block file and trying to get in each other’s way. If this is not prevented by, for example, file-level locking, data corruption is likely.
Instead, I believe the RPC API will allow you to switch between two or more wallets using a single bitcoin-qt (or bitcoind) instance. loadwallet
Command.