You basically have two options to set this up.
1. You can set this up using the visual experience composer. It will be structured a little different than what you are describing. Basically you will have two experiences with two audiences. Since its a test, Target wants to test each experience against the same audience. So its not possible to set it up as an experience with an audience vs a different experience with a different audience. It wouldn't be a fair apples to apples comparison. It would look like this.
Control:
- Local Audience
- Tourist Audience
Exp B
- Local Audience
- Tourist Audience
Here is a screen of how you get to setting up multiple audiences.

2. The other option, is to set up three different tests. So three tests each with one experience and one audience. The problem here is that Target won't be able to compare the conversion rates for you. You would have to do the comparison yourself using a spreadsheet, which I often do anyway.
Does this make sense?