Even though you have not responded to @ComplexPoint’s question about which app you’re working in, you say it has a search facility so the question now is: does that search facility support regular expressions?
This reply of mine is unlikely to give you what you’re looking for but here goes anyway.
For “fun” I created a regex to do what you asked in your original post. You can see it in action here regex101: build, test, and debug regex - take a look… The problem with this regex is that it’s tailored specifically to your example so that it would likely not work if the text you gave it was different.
In my view to employ this in Scrivener’s search/replace dialog would take more time and effort than simply getting in there and moving the sentence manually. It may be that you could get a KM macro to “drive” the search/replace dialog but I can’t explore that option for you right now.
Have you tried asking the question in L&L’s forum?
Why bother when Scrivener already has a “select sentence” facility?
From the Scrivener manual (p. 716):
Select ▸ Select Sentence As noted above, if you start with two partially selected sentences then you would end up with two fully selected sentences when using the Select Sentence command. Given the wide range of languages, writing styles and methods, right, wrong or just creative—grammatical constructs such as sentences can only be estimated.
And you can assign a keyboard shortcut to it using the usual MacOS procedure.
Of course there’s also the “move” facility built-in to Scrivener…
Selecting word, line, and paragraph are common functions in many editors (particularly programming editors), however Scrivener is the only app I've ever seen to add “Select Sentence” to that group.
