Well, you talked about local server, which is Legacy not IoT, and Bridge, which is also Legacy and not IoT.
Posting code snippets, and not providing the information about which version of Blynk you are using - which is requested when you create a topic, means we have to make assumptions, and everything you’ve posted leads to the assumption that you are using Legacy not IoT.
If you want to transfer data from a salve device to a master in IoT the. You can use Automations in some situations.
If Automations don’t provide the functionality you’re looking for then the HTTP(S) API can be used to simulate the Bridge functionality of Legacy…