Stolas didn't use teleportation; the only time in the series he explicitly uses teleportation is when he expels Blitzø from his mansion, and it has both a distinctive effect and sound that aren't shown in that scene.
Yes, Stolas's solo feat could be considered spaceflight speed (even though we have no evidence that Stolas gets fast in space), but together with Emily's, it's consistent.
Emilly's feat is strange, but still, she reached Alastor by a good margin before the MoL beam, and apparently reacted to the beam sufficiently for Alastor to be far away from her after being hit, and only have one wing damaged. On the other hand, it's a rather confusing feat, and alone it wouldn't hold up on a scale, but together with Stolas's feat, it makes sense.
It's also worth mentioning that during the song in episode 2 of HB, Stolas sees planets and the Moon being slowly pulled and destroyed by the star before it explodes as a supernova. Even if, for these objects to reach the star before the lullaby ends, they have to be relativistic at the very least. Although there's no exact calculation for this since I didn't expect Shion to do a summary 1 day after the end of the Mega CRT.
Regarding the lightning feat, it would be at least Mach 30 and at most Mach 3000; it's a good supporting feat, but it would be good to decide on a value and explain why it's there, but again, surprise CRT.
Adam's light, while meeting the requirements to be SoL, has minimal concussive impact (or at least that's what CGMs say), so it cannot have that speed.