Batch convert to be same bit depth as original

[revadiaz]

Version: XnViewMP 0.93.1
OS: Windows 10 64-bit

Currently, the batch convert from 8-bit grayscale image is always 24-bit. So the result file size is bigger even though i do scaling down resolution. My workaround is add an action to change bit-depth. But for a batch with a lot of different bit-depth files, this become frustrating as i need to select each file manually. Nested folder image will be impossible. Could you please make conversion and some action (i.e resize) to be same bit-depth as original?
Thank you.