Add intro and outro to multiple files (batch)
This is indeed possible with After Effects via its Scripting Interface, though this is a bit harder to use than Photoshop Actions. You will need to learn Adobe ExtendScript and how to use it in conjunction with After Effects.

For this particular job I'd suggest a different approach using FFmpeg. It's an open source video encoding and processing tool that is used for many video automation tasks in the industry.
You will have to write a script here aswell but that would be a LOT easier and shorter than digging into Adobe ExtendScript in conjunction with After Effects.

Assuming you have an rendered video of your intro, outro and main media file in the same codec. You can then use the concat command in ffmpeg to mux the three file into one, which results in a joined video without any re-encoding of the source media.

Here is a tutorial on how to do that in the Linux bash but you can do the same thing with AppleScript or Windows Batch script. You want to generate a filelist like shown in the tutorial:

file '/path/to/intro.mov'
file '/path/to/main.mov'
file '/path/to/outro.mov'


You would generate this filelist for every main media file and only change the path for your main media file for every "export".

Just for reference, this is the final command you would then use:

ffmpeg -f concat -i filelist.txt -c copy output.mov


How the script part looks that comes before the FFmpeg command that generates the file list, completely depends on your operating system and or choice of scripting language.
Note that you don't have to use the source codec, instead of doing copy you could also encode the output file into a different codec by specifying a codec with encode setting instead. 

For example:

-c:v libx264 -preset medium -f mp4