How can I sort my Groups within the Favorites Sidebar 
Not possible as of yet. You could send a feature request to DTech.
Well, automatic sorting is not possible yet but you can manually drag things around in the sorter. If necessary, make it larger to create some empty cells. Considering there will only be a handful items in your Sorter, there is no need to sort according to whatever criterion.
I read the OP’s request that (s)he wanted to sort the items added to the Favorites section of the Sidebar, not auto-sort the items added to the Sorter.
Yes exactly, I need to sort my Favorites within the Sidebar. But as “korm” stated (thank you) this is not possible. And I will send a feature request to DTech… 
Oops, sorry for the misunderstanding.
Anyway, thank you for supporting 