How can I add extra PBR normal map on this specific situation?

Hi, I’m trying to achieve a watercolor-like stylized look and I found a way that manipulates normals. But the thing is, I also want to add PBR normal maps but don’t know how.

How can I add a seperate PBR normal map on this material?

Here’s the node setup:

You can’t, realistically speaking. You can easily mix two normal maps together with a Mix node set to color, a pair of Vector math nodes set to Add and Divide, etc… but the end result is going to be a mess

That said, here’s your node setup mixed with a PBR normal map:

I see. I have to try another method to do my material then.

Well, thank you so much for answering!