#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?U)<span class="CharOverride-7">(.*)<\/span>"
Local $sString = "<p class="2"><span class="CharOverride-7">A book title</span><a href="https://aaa.net"><span class="CharOverride-8">https://aaa.net</span></a><span class="CharOverride-7">.</span></p>" & @CRLF & _
"" & @CRLF & _
" <p class="2"><span class="CharOverride-7">Another book title</span><a href="https://aaa.net"><span class="CharOverride-8">https://aaa.net/</span></a><span class="CharOverride-7">.</span></p>" & @CRLF & _
""
Local $sSubst = "$1"
Local $sResult = StringRegExpReplace($sString, $sRegex, $sSubst)
MsgBox($MB_SYSTEMMODAL, "Result", $sResult)
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm