According to the install log you posted, the plugin was successfully installed. According to the startup log you posted, calibre started correctly after the installation.
I set my calibre language to French and I was able to see that the plugin installs with the translated name. This is a bug and will be resolved, but it is very low priority since everything functioned properly: the plugin was in the list of installed plugins, the plugin remained installed after many restarts of calibre, conversion options could be set, and books could be converted.
According to the install log you posted, the plugin was successfully installed. According to the startup log you posted, calibre started correctly after the installation.
I set my calibre language to French and I was able to see that the plugin installs with the translated name. This is a bug and will be resolved, but it is very low priority since everything functioned properly: the plugin was in the list of installed plugins, the plugin remained installed after many restarts of calibre, conversion options could be set, and books could be converted.