I can read a lot of questions about this topic but with different interpretations.
I’m going to change my permalink structure

from
http://www.example.com/%year%/%monthnum%/%day%/%postname%/ to http://www.example.com/%postname%/

So new posts will be natively in the new url format, about old posts I’m going to add just one row in the .htaccess file, following the suggestion coming from yoast.com

RedirectMatch 301 ^/([0-9]{4})/([0-9]{2})/([0-9]{2})/(?!page/)(.+)$ https://www.example.com/$4

After few test in another small website, it seems to work.

My questions are:

1. Is finally the “best way” to do it in terms of avoiding SEO impact? (I see a lot of people using redirect plugin..someone says that wordpress does it automatically after structure changes..someone add in htaccess one row for each link even if the structure is standard..)

2. Should I do additional actions after change .htaccess and “wordpress permalink structure”?

Sorry if there are similar question, but as you can imagine it would be very risk change.
Thanks!!!