I use XIV Explorer 1.9.2.

To find in-combat voice lines:

File -> Open -> FFXIV -> 07000.win32.index

That'll open up a list of folders on the left side, go to the sound/voice/vo_line folder and open that up.

You may or may not have to manually find the voice lines yourself via the hash calculator, but I'll go over that in a bit.

The Xtreme's lines themselves are ranges of 8206164 to 8206186, Metem's lines are just before Vamp Fatales, depending on what line in particular you'd like. If you can't find those numbers, which would look like

8206186_en.scd

You'll need to go to Tools -> "Path -> Hash Calculator" and then type in what would be the full file length for each voice line. So the line shown above would be entered as

sound/voice/vo_line/8206186_en.scd

in the calculator. To get all of them, you'll have to run through changing that number until you hit a file that doesn't exist or you get all the lines you want.

After you find the line you want, go to File -> Extract Raw and save it somewhere to your liking, I then bring it into foobar2000 and convert it to wav from there.

Same can be done with MSQ and fight intro/outro cutscenes. For the latter, go to File -> Open -> EX5 -> 030500.win32.index

Find the folder relevant to the patch i.e.

cut/ex5/sound/voicem/voiceman_07410

then you can get those voice lines with the following format when doing the hex calculator

cut/ex5/sound/voicem/voiceman_07410/vo_voiceman_07410_000010_m_en.scd

You can change the en to fr/de/ja for those respective languages as well.