Creating a batch setup with custom audio settings

[Takaji]

I'm just getting started with batch processing and have a few questions.

How can I batch process a bunch of video files in a specific folder, using the same settings for each video file?
I've already set up my default save paths, but it seems that when I import a video, I need to go to the Audio tab and click the + (Add current), otherwise the audio does not get encoded in the video (note that in the Base tab, I've set audio processing to "custom.")

Do I need to manually import each file and then click the + button, or is there a way to do this automatically for each video file in the folder?

Thanks!