visual-regexp for Emacs is like
query-replace-regexp), but with live visual feedback directly in the buffer.
While constructing the regexp in the minibuffer, you get live visual feedback for the matches, including group matches:
Hosted under https://github.com/benma/visual-regexp-steroids.el/.
This is an extension to
visual-regexp which lets you use an external, modern regexp engine for searching and replacing. The package comes with an interface to Python’s regexp engine and pcre2el-support out of the box.
The package can also be used to power
isearch-backward-regexp with a modern regexp engine. See the project page for details.