There is a new pull request by krkk against master on the void-packages repository

https://github.com/krkk/void-packages libqmatrixclient
https://github.com/void-linux/void-packages/pull/15195

libqmatrixclient: update to 0.5.2.
0.5.x releases keep the previous library name, libQMatrixClient.

A patch file from https://github.com/void-linux/void-packages/pull/15195.patch is attached