I am creating a podcast, and I want to use 3 microphones with the line-in microphone jack. I was planing on using this:

I was wondering if there was something like this:

but for microphones, this seems like the easiest and cheapest way to do it.

also would this method work for audacity?

thanks for reading and thanks for the advice/help if you can give it.

What kind of microphones? In detail.
For computer microphones, I’d say not in any useful way. Not only does the sound have to go from the microphone down to the computer, but the 5v battery has to go from the computer back up. That’s the one that will kill you. That battery will be shared between the three microphones and the mics get quieter and quieter as that voltage goes down. Also, the sound will mix on its way to the computer and that will be three times lower than it would normally be.

Couple that with the average sound card which is blisteringly terrible on a good day, and I doubt you would get anything useful.

You didn’t encounter this yet, but you may also want to change the volume of one microphone because only one performer is a little quiet. Sorry. Can’t do that. Can’t fix that in post, either.

But I guess technically, it would work.

If you were using much beefier microphones that either had their own power or did didn’t need power, that would go much better, although still nothing to brag about.