Custom AnimGraph Node not working on Standalone Game or Packaged Build

Use this setup for MyCustomAnimNodes.uplugin and standalone will work:

"Modules": [
       {
          "Name": "MyAnimNodes",
          "Type": "Runtime",
          "LoadingPhase": "PreDefault"
       },
       {
          "Name": "MyAnimNodesEditor",
          "Type": "UncookedOnly",
          "LoadingPhase": "PreDefault"
       }
    ]