Current emby version shiped in this package link
App can be installed by YunoHost by running following command:
$ sudo yunohost app install https://github.com/vibrantleaf/emby_ynh
$ sudo yunohost app upgrade embyserver -u https://github.com/vibrantleaf/emby_ynh
Emby server is a non free app. More info here: https://emby.media/terms.html