This plug-in is provide "animation mirroring".
- Clone the repositry under "{UnrealProjectPath}/Plugins" directory.
- Right click on the {UnrealProjectPath}/{UnrealProjectName}.uproject" file and select "Generate VisualStudio Project files".
- Build with generated sln.
- Open AnimGraph of AnimBlueprint and add "Mirroring" node.
- Create an asset of "Mirroring Data" with "Details - Settings" of the added node.
- Open the added asset and set "Name Rule" to "Tail Match", "Bone Name" to "_l", "Pair Bone Name" to "_r" and "Axis" to "XAxis". This will invert the bones of the names whose names end with "_l" and "_r".
- Change "Default Axis" to "XAxis". Now nodes other than pairing mirror on the X axis.