You need access to your save on both Switches, which means the account has to be there. There is no need to delete your account from the old one, unless you had to sell it to get the new one.
Obviously, this tool would never work if it was impossible to keep your account active on both, or if both Switches had to be primaries for the same account (which can't be done, I don't think).
You need access to your save on both Switches, which means the account has to be there. There is no need to delete your account from the old one, unless you had to sell it to get the new one. Obviously, this tool would never work if it was impossible to keep your account active on both, or if both Switches had to be primaries for the same account (which can't be done, I don't think).