You must have another wallet (address2) programmed as an ETH balance tracker at address1 and as the main reservoir of gas costs, set a minimum balance for address 1 as a trigger and send ETH automatically if the minimum balance has been exceeded. Thus, addresses2 become an exception that ETH sent to address 1 will not be sent automatically to another address.
This looks like the way a smartcontract exchange works. Are you building it? maybe you need to discuss specifically in the project development section

If you are looking for a smartcontract developer, you must post in the services section. Please be careful of anyone about the script code, at least you should know basically how the smartcontract script works.