I’ve found that it goes alphabetical by what the source is named. 

What you call your sources through the API doesn’t matter, as you then get to rename them with the phrases tool. 

TL;DR solution: rename your source inputs in the API to be after community aplphabetically

Here’s an example of how we solved this: 

• We use the out-of-the-box Skilljar integration
  • This provides Course-level (macro-content) federated search, but the individual lessons within them
  • the source with this integration is called “skilljar”
  • (From your example, it looks like that same thing is happening with your Academy courses appearing lower on the list)
• We also index the lessons from those courses in skilljar so that the micro-content is searchable as well
  • We use the federated search API for this
  • When we discovered the issue you’r talking about, our lessons (source = lesson) was appearing above the courses because of the alphabetical order

To solve it we renamed the source for our lessons to tlesson, putting it alphabetically behind skilljar and right below. Then we renamed the source phrases and it now shows as: 

• Community
• Academy Courses
• Academy Lessons

Thanks @DannyPancratz!  I assumed they would be alpha, but I checked the sources, they are like this. before renaming in Phrases.

Yes, it’s alpha after the Federated.Search.

Although your LM Academy Courses is throwing me off. 

Update: PROBLEM SOLVED!  For anyone else who may have this issue, and not be technical (like me) the above source code names just the names displaying in the Community before I renamed them.  After some digging, we found the list above sorts by the last .word “Federated.Search” is not what it sorts by, for Blogs, was “.blogs”

Thanks again @DannyPancratz !