Example hits by pro's:

Low elbow spikes:

Steven van de Velde:
https://www.youtube.com/watch?v=-S-DbD-048I&t=1283s (kind of wristaway)
https://www.youtube.com/watch?v=-S-DbD-048I&t=1194s (over the shoulder far off the net)
https://youtu.be/-S-DbD-048I?t=1946 (far off the net)
https://youtu.be/-S-DbD-048I?t=1407

David Åhman:
https://youtu.be/xqpYQXvO788?t=11
https://youtu.be/D_vFa8PLQxg?t=631
https://youtu.be/xqpYQXvO788?t=22 (wristaway)

Evandro (has a very distinctly low elbow):
https://www.instagram.com/p/B95DCLbFVmh/
https://www.youtube.com/watch?v=bWnCU9tZdFI

Viacheslav Krasilnikov:
https://youtu.be/HPvDApYl3XQ?t=116
https://youtu.be/WZsgYHsrhFI?t=6130 (a bit off the net)

Christiaan Varenhorst:
https://youtu.be/-S-DbD-048I?t=1163

Alexander Brouwer:
https://youtu.be/D_vFa8PLQxg?t=770

High elbow spikes:

Cherif Younousse:
https://youtu.be/OVSwiWwXAQM?t=187

Two players from highlight video (not sure exactly who they are):
https://www.youtube.com/watch?v=9jM3wEYpxx8&t=225s
https://www.youtube.com/watch?v=9jM3wEYpxx8&t=318s

Anders Mol:
https://www.instagram.com/p/Bz_SBUZF57e/ (high elbow/spaghetti wristaway)

High elbow by a woman (not sure exactly who) for a changeup from my other examples (last hit in the rally):
https://www.instagram.com/p/B9GqDwVFixy/

Other interesting hits:



Only example of a "roundhouse armswing" I have:
https://youtu.be/JWB89aon1o0?t=19

Something I'd consider a "low elbow" armswing (although not as distinct as some other players) by both Riley and Maddison McKibbin: https://www.instagram.com/p/BWN8XzfF_w0/
https://www.instagram.com/p/BULDVEulJJZ/

Maybe the highest elbow swing I have found. (Comment: I don't think he goes as far back as the "natural stop", but I believe he is very strong and stable in his body instead so he can still put a lot of power into the ball.)
https://www.instagram.com/p/CCyhHIEnrsb/

Martin Appelgren something between high and low elbow? Very efficient at least, no matter how high the elbow actually is..
https://www.youtube.com/watch?v=7fFnos2hTmw

If we allow ourselves to study also indoor volleyball players and not just beach players, we have 3 of some of the most legendary spikers using a low elbow armswing:

Earvin N'Gapeth: https://www.youtube.com/watch?v=PBxbxgh_YmE
Mireya Luis: https://www.youtube.com/watch?v=8zFZxBhqYog
Pat Powers: https://www.youtube.com/watch?v=KMd1gM1tfg0

Have any good examples of players (or yourself!) with interesting/distinct techniques in mind? Don't hestitate to post them in the comments for the high/low elbow armswing video (https://youtu.be/Plaz_wekXUk), we can all learn something from them! :)