flycheck-clj-kondo VS lispy

My best suggestion here would be clj-kondo with flycheck-clj-kondo in Emacs. I really can't recommend it enough and would have killed to have it when I was learning Clojure. Not only will it underline all of those references to (now) undefined vars, but it can tell you about numerous little mistakes like mixing up arguments orders in (say) sequence functions, misplaced docstrings that get discarded, style conventions, etc. It's staggering how good it is even for a language as dynamic as Clojure.

Some killer features in Emacs, which I would recommend checking out, is imenu and movement by s-expression (functions like forward-sexp). These are built into Emacs and make navigating across or inside blocks of code very easy. I have also seen that lispy, which is usually used for Lisp code also supports Python. Again I can't speak to any specifics about how well these things work for Python devs.

While writing other programming languages with LSP, it formats the buffer once I hit save. Is there any way to make https://github.com/abo-abo/lispy do some equivalent behaviour?

Without any order magit, lispy and minions.

I don't know cider, but...I found lispy mode a revelation in making the easy, easier.

The level of interactivity in your emacs determines how easy trying emacs-lisp becomes. I suggest checking out https://github.com/abo-abo/lispy, it makes it easy to look up documentation (C-c 1 I believe) and evaluate S-expressions on the fly (keybinding is e). Also C-h f, C-h k, C-h v are always very helpful. Also check out helpful (the package), selectrum, marginalia, prescient, etc.

Emacs seems to attract quite a lot of people who want structural code editing. We now have * paredit * smartparens * evil-cleverparens * lispy * symex * combobulate (more?)

Obviously, we have packages like Paredit and Lispy, recently we got SymEx, but these are all for the Lisp family of languages, where syntactic redundancy is very high because of the homoiconicity.