Izanagi is a justu which derives from the yin side of creation of all things. The yin side of COAT allows a user to create shape from nothing. Perhaps calling it Izanagi is a misnomer, but for lack of a better term, it explains the principle quite well.
While it's effect seems to b e akin to teleportation, I do not believe it is. This is because we know that Sasuke is well associated with the yin element. Sasuke just received the yin power of the Sage of the Six Paths. This opposed to Narutos Yang power, which he has demonstrated to be able to breathe live into a person. I.E. guy and Kakashi he kept guy alive and brought back Kakashi's eye by giving it life again.
Sasuke received the yin power of COAT and above I explained it's relevance. We also know that the sharingan is heavily related to genjutsu as will as the sharinnegan. Now that Sasuke has the Sharinnegan, we should assume he gets powers that are already known to be related to it. This would therefore be some sort of genjutsu power. We this information, I think it is more accurate to say it is a form of genjutsu, because teleportation has no relation to a new sharinnegan.
I would also like to note that it also has some sort of range. Sasuke needed Tobirama to teleport him to the battle, but once Sasuke was in range he was able to use his power. perhaps it is line of sight,(probably not but still range limited) but I think it suggests that it is definitely eye related and therefore not teleportation.
Also Kaguya has the same eye and in this chapter she appaears to hvae brought them somewhere with teleportation, but I would make the same case and say she either changed the environment with a true genjutsu. Or she rewrote their location in reality. I don't think she just teleported all of them without touching them or even looking at each one.
On the tomoe disappearing here is my thread explaning it some, their may be several drawing mistakes, but I think this might explain it.
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