Yes, you can use the internal storage of QS02 to play the video, QS02 has built-in 16GB internal storage.
Please refer to the following steps:
1. Connect your USB drive via the USB splitter cable.
2. Download the "VLC File Manager" app from Google Play store.
3. Copy or move the media files from your USB pen drive to QS02.
4. Use the "VLC File Manager" app and play your video from QS02 internal storage.
*Please noted:  QS02 only supports 5V 0.5A for your external USB pen drive.