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SUMMARY: Plant immune receptors, known as NOD‐like receptors (NLRs), possess unique integrated decoy domains that enable plants to attract pathogen effectors and initiate a specific immune response. The present study aimed to create a library of these integrated domains (IDs) and screen them with pathogen effectors to identify targets for effector virulence and NLR–effector interactions. This works compiles IDs found in NLRs from seven different plant species and produced a library of 78 plasmid clones containing a total of 104 IDs, representing 43 distinct InterPro domains. A yeast two‐hybrid assay was conducted, followed by an in planta interaction test, using 32 conserved effectors from Ralstonia pseudosolanacearum type III. Through these screenings, three interactions involving different IDs (kinase, DUF3542, WRKY) were discovered interacting with two unrelated type III effectors (RipAE and PopP2). Of particular interest was the interaction between PopP2 and ID#85, an atypical WRKY domain integrated into a soybean NLR gene (GmNLR‐ID#85). Using a Förster resonance energy transfer‐fluorescence lifetime imaging microscopy technique to detect protein–protein interactions in living plant cells, PopP2 was demonstrated to physically associate with ID#85 in the nucleus. However, unlike the known WRKY‐containing Arabidopsis RRS1‐R NLR receptor, GmNLR‐ID#85 could not be acetylated by PopP2 and failed to activate RPS4‐dependent immunity when introduced into the RRS1‐R immune receptor. The generated library of 78 plasmid clones, encompassing these screenable IDs, is publicly available through Addgene. This resource is expected to be valuable for the scientific community with respect to discovering targets for effectors and potentially engineering plant immune receptors. Significance Statement: This work provides a library of 104 unique integrated domains cloned from seven crop and model plants. It allows the exploition of NLR gene evolutionary diversity for the detection of pathogen effector virulence targets and putative effector–NOD‐like receptor (NLR) pairs. When screening for interaction with conserved Ralstonia pseudosolanacearum type III effectors, we uncovered an atypical WRKY domain integrated in a soybean NLR as a target of PopP2. [ABSTRACT FROM AUTHOR]