They are slowly disappearing as the years pass, but there are some still about, most, if not all of the American ones have called it quits, however, quite a few remain in Asia and to some extent Europe.
Some (mainly China & Turkey) are preceded with three or four "buzz" tones before the call sign in CW is transmitted, the call is only transmitted once. "XSQ" has three buzz tones whilst "XSG" four whilst "XSV" has four "chirps" instead of buzz tones.
The South Korean ones have a standard lengthy format.
SVO Olympia Radio from Greece is 10Kw. Transmits "de SVO" with no preceding buzz tones.
TAH from Istanbul, Turkey is 10Kw. Has four preceding buzz tones then "TAH" in CW.
HLG, HLO, HLW etc are 3Kw to log periodic. Format is "CQ CQ CQ de HLG HLG HLG QSX 12MHz K" as per call sign and frequency.
4XZ in Haifa, Israel has a standard format "V V V de 4XZ 4XZ", often transmits military type traffic.
Be interesting to find out what people are hearing, will start off with some loggings and will add to it and thus build up a list:
2.680MHz CW 4XZ 1549z Haifa, Israel Military/Navy 319 report.
4.212MHz CW XSQ 1555z Guangzhou, China 589 report.
4.215MHz CW XSG 1643z Shanghai, China 579 report.
4.216MHz CW TAH 1640z Istanbul, Turkey 519 report.
4.219MHz CW XSQ 1600z Guangzhou, China 579 report. (Heard as "XSG" Shanghai in January 2020)
4.331MHz CW 4XZ 1548z Haifa, Israel Military/Navy 539 report.
6.316MHz CW XSQ 1050z Guangzhou, China 569 report.
6.329MHz CW XSQ 1141z Guangzhou, China 599 report. (Heard as "XSG" Shanghai in January 2020)
6.607MHz CW 4XZ 1715z Haifa, Israel 539 report.
8.417.5MHz CW XSV 1015z Tianjin, China 559 report.
8.419MHz CW XSV 0856z Tianjin, China 539 report.
8.424MHz CW SVO 1755z Olympia Radio, Athens, Greece 559 report.
8.425.5MHz CW XSG 1711z Shanghai, China 569 report.
8.431MHz CW XSQ 1810z Guangzhou, China 559 report. (Heard as "XSG" Shanghai in January 2020)
8.431MHz CW TAH 1811z Istanbul, Turkey 529 report.
8.433MHz CW XSG 0855z Shanghai, China 569 report.
8.435MHz CW XSQ 1809z Guangzhou, China 569 report.
8.484MHz CW HLG 0950z Seoul, South Korea 569 report.
8.636MHz CW HLW 0948z Seoul, South Korea 589 report.
12.613MHz CW XSQ 0810z Guangzhou, China 559 report. (Heard as "XSG" Shanghai in January 2020)
12.622.5MHz CW XSQ 0805z Guangzhou, China 539 report.
12.637.5MHz CW XSG 0844z Shanghai, China 559 report.
12.648.5MHz CW XSQ 0806z Guangzhou, China 559 report.
12.843MHz CW HLO 0455z Seoul, South Korea 519/529 report.
12.916.5MHz CW HLF 0457z Seoul, South Korea 419 report.
12.923MHz CW HLW2 0500z Seoul, South Korea 319 report.
12.935MHz CW HLG 0811z Seoul, South Korea 419 report.
16.854MHz CW XSQ 0837z Guangzhou, China 539 report.
16.880MHz CW XSQ 0836z Guangzhou, China 539 report.
16.898.5MHz CW XSG 0840z Shanghai, China 519 report.
16.910MHz CW HLJ 0439z Seoul, South Korea 319 report.
16.990MHz CW HLO 0423z Seoul, South Korea 419 report.
17.130MHz CW HLW 0358z Seoul, South Korea 319-419 report.
22.611.0MHz CW HLF 0220z Seoul, South Korea 519 report.
Note: During late December 2019 and early January 2020 some "XSQ" Guangzhou Radio transmissions were changed to "XSG" Shanghai Radio, whether this is a "shared" frequency with alternating call signs or a permanent change? Also some preambles have been changed to "de" prior to call sign eg: four buzz tones hence "de XSG" has been noted from late November 2019 onwards.