Nothing has changed in Bubble since that post, so the advice there still holds true.
It’s still not possible to sort data on related field values, so there are only 2 ways to do this.
Load ALL the data to the page then sort it using some custom Javascript or a plugin (fine for small amounts of data, but no good if your database is large).
Add a number field to the DB just for sorting (as annoying as it is… this is the correct way to do this in Bubble in most cases).