You can’t overwrite the tag in the plugin itself because currently tags created by the plugin are given higher precedence than those added with the tags option #3362.
The best way I can think to handle this now is with the override processor plugin:
[[processors.override]]
namepass = "http_response"
[inputs.processors.tagpass]
server = ["https://media.3ds.com/*"]
[processors.override.tags]
server = "server1"