Is it possible to have physics simulated objects behave kinematic to objects grabbed by physics handle?

Development Programming & Scripting Blueprint
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I have solved the issue by adding an extra cube, two collision channels and playing around with collision, simulate physics and collision channel settings.

Collision Channels

I added 2 new collision layers: InvisibleCollider, GrabbedObject

Grabbable Cube BP:

1. ParentCollider

  • This is the main parent of the BP. It is a box collider with collision object type as InvisibleCollider and it is set to “Ignore” any InvisibleCollider.
  • This has simulate physics enabled.

2. VisualCube

  • This is a cube that is child of the ParentCollider component.
  • This is the cube that is visible by default for all grabbable cubes.
  • This one has simulate physics off so that any grabbed object will not affect it.
  • Auto weld is disabled.

3. GrabCube

  • This is the cube that the character will use for grabbing.
  • Collision is set to false by default and visibility is off.
  • Collision object type is GrabbedObject
  • Auto weld is disabled.

Events

1. Grab object

  • Enable physics, visiblity an simulate physics for GrabCube
  • Disable collisions for the ParentCollider and VisualCube
  • Disable visibility of VisualCube
  • Disable simulate physics for ParentCollider

Grabbed object: Because of the settings above, the visual cube and its parent collider will not work now in the grabbed cube.

Other objects: Even though the ParentCollider has physics enabled, it also has ignore for grabbed object, so the grabbed cube will not affect it. The VisualCube on the other hand has simulate physics disabled, so that will also not be affected by the grabbed object. Setting auto weld to disabled makes sure that it does not start simulating along with its parent, the ParentCollider.

2. Drop object

Mostly just the opposite of grab object with one extra step - Copy the location and rotation from GrabCube and assign to VisualCube.

Final result:

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