Moving duplicate item to another group or board

Hello!
Background: I have this “Main board” wherein tasks from different “project boards” gets populated. The main board functions as a repository, thus there is a possibility of a task duplication.
Goal: I want to retain the first item that gets populated to this main board and archive or move succeeding duplicate tasks to another board or group.
What I’ve done: I have a column that identifies a duplicate task - [Project Name: Task - Doer] - if the text have the same project name, task name, and doer it means it has a duplicate. (see attached highlighted in red)
Duplicate_jul 15

Problem: How do I archive or move succeeding duplicate tasks from this board/group?

Appreciate if anyone has a similar case and has a solution or workaround. I want a native monday solution as much as possible since our firm doesn’t want to incur any additional costs from integrations/marketplace apps. Thank you!