I processed a bunch of images taken from our Micasense Dual sensor (red and blue sensors) with Pix4DCloud. The index files generated are causing quite a bit of confusion.
First question - why are there 2 files per band?
I assume these transparent reflectance files are from both the red and green bands - a total of 10 bands.
Did you export those files from PIX4Dcloud or PIX4Dmapper? because they refer to the reflectance bands in tiles (smaller files), which should be obtained with PIX4Dmapper or downloading the “Orthomosaic” from PIX4Dcloud, which I don’t see in your case. As a solution, you can Merge those tiles for each band in QGIS to obtain just one per band.
The “transparent” stands for the values for the pixels that have no value in your dataset, you should see the ortho without any black or white border. This is an export option.