The OTG Micro USB 3-in-1 of KiwiBird and Midgard are outwardly very similar and both work on the Samsung Galaxy Tab 3 8.0 only partially. USB flash drive works, but SD and MicroSD cards do not work, I've tested with 8GB and 32GB repeatedly.
With "Trust TV connection kit with card reader" function, the SD and MicroSD cards on the Galaxy Tab 3 8.0 without problems.