thanks for comment, ya its simple and I was kinda shocked that every wallet developer hasn't considered this simple option.
New feature - if Wallet A received a new deposit within x of time auto send to new wallet B address.
The reason you haven't seen either implemented in a widespread fashion is because both features are extremely insecure. You're actually seeing a move within the bitcoin industry in the complete opposite direction. There are no private keys at all stored online anymore, making these features impossible.