Of course i want to spend time on it, but all the methods i've tried have failed. Hence why im here asking for a push in the right direction.Of course it's possible for a plugin to do that. Now if nobody wants to spend free time on it, I guess you should look for someone to code it for you.
Basically, you could find an existing working routine and 'translate' it into csharp. Else you'll have to think about your own way to filter items.
Use LUA event handlers in HB API to get inventory updates and LUA injection to drop an item.