#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?m)^(.*) (\w\w\w) (\2)$"
Local $sString = "A Nightmare On Elm Street 720p Bluray X264-Pahe In mkv mkv" & @CRLF & _
"Austin Powers International Man Of Mystery 480p Bluray 300mb-Pahe In mkv mkv" & @CRLF & _
"Death_warrant_1990_720p_bluray_x264_750mb-Pahe In mkv mkv" & @CRLF & _
"Die Frau Des Polizisten 720p Bluray X264-Pahe In mkv mkv"
Local $sSubst = "\1.\3"
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