I'll also add the course from The Great Courses - 'Building Great Sentences: Exploring the Writer's Craft' by Brooks Landon.
Just the audio version is sufficient, especially if you can listen to it on a daily commute. They give specific advice on how to simplify sentences that have multiple dependent clauses into a more compact form, which can be particularly useful for technical writing.
"The Elements of Style does not deserve the enormous esteem in which it is held by American college graduates. Its advice ranges from limp platitudes to inconsistent nonsense. Its enormous influence has not improved American students’ grasp of English grammar; it has significantly degraded it."
Probably a more brutal takedown than deserved but I'm not at all sure it's wrong.
The article is needlessly contrarian and negative. The book is useful to get students or anyone playing a trade writing from 3/10 to a 7/10. A lot of critics lose sight of this.
It's a great book to use for guidelines to start with when building out your own style. If youre an editor and want to use it to compell others to write with a style, it's less useful.
To some it will be too obvious. But English speakers (especially English as a second language people) outside the US have often never heard of it.