https://wccftech.com/elden-ring-new-mod-mounts/

A new Elden Ring mod that has been shared online this week allows players to mount horses other than Torrent as well as other creatures.

The More Mounts mod requires modding the regulations file, so it cannot be used to play online. Additionally, all mounts, including horses, cannot jump, so there is no real advantage in using them in place of Torrent.