EasySounds has one offering

https://easysoundsshop.de/en/yamaha-seqtrak/216/seqtrak-cr

I can't vouch for it personally but I think they provide one demo sound.

Also, I've read that the engine is the same as the Reface DX and that seqtrak has some of the reface patches. Don't know if you can find and then load reface patches to the seqtrak.

Loading Reface DX sounds in Seqtrak would be nice, but pre-made drumpatterns are a totally different request.

Recently I'm also thinking about loading Reface DX patches to the Seqtrak DX track... I've gone through the midi data info of the Seqtrak and the Reface DX, only found out that the bulk dump on the Seqtrak cannot be used to dump only the DX track sound, maybe I'm new to reading those midi data info, gonna figure things out later...
Seqtrak's DX sound midi parameter layouts are not exactly like the Reface DX though, Seqtrak has more paramater labelled 'reserved'.
I find out that you can send parameter change info to change the DX track parameters accordingly to modify the sound quicker... Perhaps that's a workaround of sending Reface DX sound sysex to the Seqtrak by sending multiple(lots of) parameter change. 🤣

PS: I've also posted on IdeaScale Community about adding Reface DX patch compatibility to the Seqtrak. 😊

The data list doc (p.93) says you can dump a 1) project, 2) sound or 3) a sampler element. Keep in mind we don't have a Seqtrak to experiment with but are very familiar with the bulk dump process on some synths.

To execute 1 PROJECT / SOUND / SAMPLER ELEMENT bulk dump request, designate its corresponding Bulk Header address.
For the information about "mm" and "nn" shown in the following list, refer to Parameter Change Table (Bulk control) below.

Looking at that 'Bulk Dump Block' table shows it contains 3 'Bulk Header' entries and their Hi, Mid, Lo addresses to use. There is an entry for 1) project, 2) sound and 3) sampler element.

The basic process to use SysEx for a dump request is to send a SysEx command using the format shown on p.90 in the (3-5-4) DUMP REQUEST SECTION

F0 43 2N 7F 1C 0C aaaaaa aaaaaa aaaaaa F7

The three sets of 'aaaaaa' correspond to the Hi/Mid/Lo address for the block header of the object you want to dump.

Those Hi/Mid/Lo addresses are listed on p.95 in the 'Parameter Change Table. Look at the 1st table entry and it shows that address '11 00 00' will dump the project that is currently in the edit buffer. So you would load the project of interest before sending the command. The command itself would be:

F0 43 2N 7F 1C 0C 11 00 00 F7  --- where the aaaaaa aaaaaa aaaaaa from the example was replaced with the Hi/Mid/Lo values from the table on p.95

The 3 table entry is 'Sound Edit Buffer Part nn (nn - 0-10)' and you would use that address to dump the current sound for a specific part. Of course you need to load that part/sound before sending the command.

The Hi/Mid/Lo for part 2 would be 11 02 01 -- the '01' represents part 2 since the data is zero-based (0-> part 1, 1-> part 2, etc).

Get one of those simple examples working first.

The table shows 16 entries for user sounds: 'Sound User 1 (nn = 0-127), . . ., 'Sound User 4 (nn = 0-127)'

There are 128 possible sounds for each of the 16 user banks. So the first 128 'user' sounds will be in 'Sound User 1' and so on.

To get the 3 sound of the User 4 bank you would use a Hi/Mid/Lo address of 11 06 02.

Post back if you need more specific help with the SysEx format. Be sure to provide SPECIFIC examples of the commands you use rather than just describe what you do.