OK, it's been a few hours, so new post, instead of an edit to the existing one.
A while ago, there was a discussion in the
main thread on SB.com about the lack of standardized names for each Earth, due to the fact that the various planets each have their own way of designating them, and don't want to adopt the ones the others use, but I didn't say who uses what. I'm now correcting that:
As most of you know, Infopunk Earth goes by order of age, mostly calling itself 'Earth One', Dieselpunk Earth 'Earth Two', Steampunk Earth 'Earth Three', Clockpunk Earth 'Earth Four', and Fantasy Earth 'Earth Five'.
Dieselpunk Earth, OTOH, goes in order of position in the line of Earths, with itself as 'Earth One', Fa-Earth as 'Earth Two', Inp-Earth as 'Earth Three', Clp-Earth as 'Earth Four', and Stp-Earth as 'Earth Five'.
Steampunk Earth also goes in order of position in the line of Earths, with itself as 'A-Earth', Clp-Earth as 'B-Earth', Inp-Earth as 'C-Earth,' Fa-Earth as 'D-Earth', and Dp-Earth as 'E-Earth' (though astronomers sometimes switch the letter to the back instead of the front, saying 'Earth-C' rather than 'C-Earth', but that's usually a matter of language).
Clockpunk Earth does not have a sufficiently united astronomical community to have a standard set of designations, but the European astronomical community seems intent on giving the Earths individual names. It's too soon to say for certain, but they seem to have mostly settled on calling their own world whatever each language called it, before, calling Inp-Earth 'Autocthonia', and Fa-Earth 'Terra' (though some want to use 'Gaia' for Fa-Earth), and are still debating what to call Stp-Earth and Dp-Earth. It's been only a few months, after all, and communication isn't brilliantly fast, even if it is a lot faster than in the Europe of our 1556.
Like Clp-Earth, Fantasy Earth lacks a particularly unified astronomical community, but thanks to Arthur's spirit-children, the Romans do know how old each Earth is, and thus have adopted a system based on age like Inp-Earth, but in the reverse order: They label their own Earth 'Terra I', Clp-Earth 'Terra II', Stp-Earth 'Terra III', Dp-Earth 'Terra IV', and Inp-Earth 'Terra V'.