Sample actions can be found at:

https://2manyrobots.com/SampleActions/YateSampleActions.html

From time to time we might dump other sample stuff, such as search templates, to the Sample Actions page.

Note sure what is happening. The import/export stuff is not 'aware' of single items. You either import all the actions in a plist file or none. If you are hearing the 'plink' something is being done. The code does not care about the source volume of the plist. The 'drag in' mode is a convenience and only works if you drag to the 'list of files' panel.

You can use 'Import Preferences File Contents....' or hold down the Shift key when dragging a plist in to view the contents.

....and...when you Import via the menu you get the chance to select which component types to import. When you import by dragging you preset the type of stuff you're interested in via 'Preferences-File List-Dragged preference file import settings'

Ah yes, the dragging of plist files and /or artwork files is one at a time. The dragging of audio folders or files allows multiples.

Each plist file is actually an action bundle as it contains all components required to run the action. As an example, when you import the Apple Music plist you get 19 actions and 1 export set. You can drag the actions to the main window's file list area in order to import (most of the samples).

There was a reason why multiple imports at a time were disallowed and it is mostly to do with the sequencing of the imports. Each import is actually a separate process. When you drag over multiple audio files the load is coalesced and is a single process. This can't be done with the action/settings imports as plist files can contain lots of non action related settings and sequencing could be an issue. The issue is determining when it is safe to load the 2nd bundle, then the 3rd etc and how you could cancel.

I could export as many as I want into a single bundle which would then import a slew of actions but it would be much harder to explain the distribution. There is another reason I don't produce a single bundle and that is folder information would be lost. As multiple unrelated actions can be exported at a time, the original folder information has to be discarded and bundles either install the actions in the root or under a single folder. It would be more than a little tough to figure out what a flat list of hundreds of actions were.

Also, some of the bundles contain conflicting custom field definitions. When importing custom fields, everything stops and you have to confirm what you will accept and possibly which version (current or new) you want to keep.

Hopefully this doesn't sound like an excuse but there really are reasons behind the decision to do one bundle at a time.

While you could do it with a Hazel script you'd have to be able to determine if Yate's UI gets blocked by a popup panel (during installation) which is asking for input. The time it would take to write the script may be more than simply dragging them over one at a time.

The most aesthetic solution would be to extend the Action Updater to allow you to select actions to have installed as opposed to simply selecting updates for actions already installed. This sort of exists already in the Multi Field Editor which can present a list of available MFE actions and can bulk install them. This is somewhere on my todo list already ... but you'll have the actions long installed before I could do it. However, this is the way to go.

Sorry I don't have a better answer for you at this time.