Go to the blueprints folder in the content browser and then select the Add New button and then select Blueprint Class. Then select actor and name the new blueprint BP_ShadowDummy and open the blueprint.

Then create a new variable called Attachments and set its variable type to Actor and set it to an Array. To change a variable to an array select the small ball icon next to the variable type and then select the array option.

Then create a new function called SpawnMeshes and set the inputs like the image below.

Next copy the image below adding all the highlighted nodes Make sure you follow it carefully not missing the inputs on the nodes!

Then select the Add Static Mesh Component node and in the details panel and copy the video below.

Then select the Add Skeletal Mesh Component node and then in the details panel copy the video below.

Next copy the image below, location at the top of the screenshot.

Next go the the BP_MasterCharacter and create a new variable called ShadowDummy and set its variable type to BP_ShadowDummy. Then create another variable called LastDummyHoldable and set its variable type to Actor.

Then copy the image below, location at the top. You will need to create a new custom event called ShadowDummySetup. Make sure you follow carefully not missing node input values!

Then copy the images below, location at the top of the screenshots.

Next go to the BP_MasterAttachment and select the Attachment Mesh component and then in the details panel under the lighting category click the down arrow to show all settings and tick Hidden Shadow like the image below shows.

Next go to the ThirdPerson_Anim blueprint and create a new variable called ShadowDummy and set its variable type to Bool. Then create another variable called DummyMesh and set its variable type to Skeletal Mesh Component.

Then copy the image below, location at the top of the screenshot.

Then copy the image below, location at the top of the screenshot.