This endpoint should return channels you follow regardless of live status.
I have checked and this works as expected for me
twitch api get 'channels/followed?user_id=15185913'
{
"data": [
{
"broadcaster_id": "26991613",
"broadcaster_login": "magic",
"broadcaster_name": "Magic",
"followed_at": "2023-02-19T15:38:42Z"
},
{
"broadcaster_id": "57047445",
"broadcaster_login": "xemdo",
"broadcaster_name": "Xemdo",
"followed_at": "2023-02-17T22:19:07Z"
},
{
"broadcaster_id": "627510124",
"broadcaster_login": "watchmeforever",
"broadcaster_name": "watchmeforever",
"followed_at": "2023-02-01T23:39:45Z"
},
{
"broadcaster_id": "58768328",
"broadcaster_login": "fried_pickles",
"broadcaster_name": "Fried_Pickles",
"followed_at": "2023-01-05T23:19:16Z"
},
SNIP
Xemdo is not currently live