Hi @DD2,
If you want to transfer files from OneDrive for business account(1) to a seperate OneDrive for Business account(2),
You could refer to steps below to acheive your requirement:
1. make sure the connection account in the "List files in folder" action and "Get file content" action are use OneDrive for business account(1).
2.make sure the connection account in the "Create file" action is use OneDrive for business account(2).
Image referance:
The expression in the "Folder Path" field of "Create file" action as below:
first(split(items('Apply_to_each')?['Path'],last(split(items('Apply_to_each')?['Path'],'/'))))
The expression in the "File Name" field of "Create file" action as below:
last(split(items('Apply_to_each')?['Path'],'/'))
The flow would run successfully as below:

Best regards,
Alice