Greasy Fork镜像 is available in English.
Extends DuckDuckGo by adding a customizable list of additional search engines for making fast searches from other engines.
I'll look into it, the previous version had it and it hasn't made it's comeback, yet.
Updated script to include suggestion, not sure of the state of the auto-update.
Thank you for your continued support.
Suggestion
Could you incorporate Mycroft Project to make it easier to add search engines to the menu?
http://mycroftproject.com/