Don't really know of any... had to look the term up as I didn't know just exactly what it was. Duelist1954 does quite a few muzzleloading videos on YouTube, but he mixes it up with modern weapons, edged weapons and a few other odd things now and then. Sure that there are others.
Ethan Yazel with I Love Muzzleloading has a good podcast. He covers a lot of topics with contemporary makers and historians. He’s on this forum, but I can’t remember his forum name (@ILoveMuzzleloading)
There’s also the Muzzle-Loaders podcast. They cover a lot of in-line stuff as it’s sponsored by Traditionals of CVA. They do venture over into traditional every now and again. More of a hunting and shooting podcast