Hi, for UE 5.1
UE_5.1\Engine\Config\BaseEditorPerProjectUserSettings.ini
then in this file, in the [BlueprintSpawnNodes] section, put
+Node=(Class=/Script/BlueprintGraph.K2Node_Knot Key=R Shift=true Ctrl=false Alt=false)
And use
Hold down Shift+R keys and left click in the graph panel to spawn a Reroute Node node.