Barusu Lamperouge
Headphoneus Supremus
Define compatible.
The socket on the ZS10 Pro is a KZ 0.75mm 2-pin “Paragraph C type”.
TRN does not follow the KZ A/B/C thing. TRN does their own thing, and they have 1 plug type. It is a 0.75mm 2-pin plug, and it’s kinda a mashup of the size of the KZ A plug with the shape of the B plug.
So if you’re asking if the TRN BT20 is compatible in the regards that it has a Paragraph C plug, then no, it is not compatible.
However, the BT20 is a 2-pin 0.75mm socket, so the ZS10 Pro will plug in and make sound just fine, so in that regard the BT20 is compatible.
The BT20 plug will stick up on the ZS10 Pro, which bothers some people but doesn’t bother others. Only you will know if it would bother you or not.
Also, you should be aware that supposedly KZ is releasing their own version of the BT20. I don’t know when or how much, but because it’s KZ you can bet that it will be available with the KZ specific ends (A/B/C).
Just to add to @Slater 's points, I'm using BT3 with my ZSN and they fit like hand to glove. Just have to push it slightly but do the job. I've used them for gymming as well and never felt insecure about the fit