I would like to know:
What rear derailleur (RD) was the "Sunrace 10 Speed 11-46T" designed to work with.
Is there a compatibility chart ?
Shimano 11 speed MTB rear derailleurs can officially handle up to 46 cogs and can be run with 10 speed trigger shifters since the pull and ratio are almost the same. I used to run RD-M9000/SL-M980 combo successfully. So you can use those with the cassette in question.
There's also Archer/XShifter electric cable drivers, these allow to run any RD given it can handle 46t cog, like RD-M9100 or SRAM XX1 Eagle.
For the record.
I found this Sunrace RD catalog
On 2nd page there is 10-speed specs.