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Are there any satellites in geosynchronous but not geostationary orbits?

Yep, lots!

Apparently there are various advantages to being synchronous even when oscillating wildly in position above/below the Earth's equator (up to +/- 60 degrees!)

After seeing the figures below in A New Look at the GEO and Near-GEO Regimes: Operations, Disposals,and Debris (found in this comment) I decided to go satellite hunting myself

left: "Fig. 3. The number and complexity of geosynchronous orbits for operational spacecraft increased significantly from 1999 to 2011. Only spacecraft whose orbital parameters are available at www.spacetrack.org are shown above." right: "Fig. 7. Highly-inclined geosynchronous communications and navigations systems (Sirius, Beidou, and Michibiki) have been deployed since 2000"

I went to Celestrak's NORAD Two-Line Element Sets; Current Data and downloaded https://www.celestrak.com/NORAD/elements/geo.txt I then propagated them all in Python using Skyfield (script below) and started plotting.

There are 513 TLEs in the list. Here are their current inclinations versus year of launch:

There are 18 satellites with an inclination greater than 19 degrees:

AMC-14 2008 20.4237 SDO 2010 29.7791 QZS-1 (MICHIBIKI-1) 2010 41.3507 BEIDOU 8 2011 58.8155 BEIDOU 9 2011 54.4339 BEIDOU 10 2011 52.1119 IRNSS-1A 2013 30.184 IRNSS-1B 2014 29.253 IRNSS-1D 2015 29.1615 BEIDOU 17 2015 53.522 BEIDOU 20 2015 53.1176 IRNSS-1E 2016 29.3272 BEIDOU IGSO-6 2016 56.5705 QZS-2 (MICHIBIKI-2) 2017 43.5483 QZS-4 (MICHIBIKI-4) 2017 40.7615 IRNSS-1I 2018 29.3069 BEIDOU IGSO-7 2018 55.0396 BEIDOU-3 IGSO-1 2019 55.0177

Here are some gratuitous 3D plots of the 18 with inclinations greater than 19 degrees:

Side view:

Top view:

"Family portrait"

Python 3 script: