To confirm what Alberto Yagos said:
- The best Princeton’s database of Byzantine translations has is Iamblichus’ Life of Pythagoras, or, Pythagoric life, which includes some sentences by Stobaeus.
- Here’s some bits translated online: The Gentle Exit ” Stobaeus Extracts Sentences and Precepts. By bits, I mean one paragraph.
- Here’s Roger Pearse, Patristic blogger, asking the question in 2010: Stobaeus, Florilegium, and getting a negative answer in 2017.
- A translation of Hermes Trismegistus is based heavily on Stobaeus: Thrice-Greatest Hermes
- This is a review of a translation of one extract of the Eclogues: Bryn Mawr Classical Review 2000.02.37.
The complete anthologies by Stobaeus, pretty clearly, have not been Englished.