Dark launch for some plugin parameter

I have run 10 kong nodes in the currrent system. And I have written 3 custom plugins and apply them to all of the kong nodes and publish to the online machines. But now, some of the parameter should be modified, And I can not ensure the parameter is totally right. Is there any gray release/Dark launch method for some kong node?

If the parameter is not stored in the database, then you can change the parameter on a single Kong node and test your hypothesis.

But the situation is stored in the database. Is there any other solution for this?
Maybe I should set the parameter in the code for a single Kong node to test this feature ?
Is there any develop plan for Dark launch?

Yes.

You can use Kong in-front of Kong to solve this problem. The Kong in-front can redirect part of the traffic to an experimental Kong cluster.