Outland Inscription

Outland Inscription seems to work a little differently from "Classic" Inscription 1-300. While the "classic" ink glyphs remained orange for me the entire time I was leveling through that to 300, even those made with the first tier Moonglow Ink, Outland glyphs are yellow as soon as you have them.

As of the way things currently are in BfA Inscription (it's Oct. 12th, 2018), I came to Shattrath to learn Outland Inscription from one of the bookcases in the Scryer's Library as a newer character who has not swayed my faction either way with the Aldor or Scryers. From the "Inscription" bookcase I was able to learn:

Ethereal Ink (green when you train it, turns grey at 5/75 skill level)
Research: Ethereal Ink (stays orange the entire way to 75/75)
Scroll of Intellect VI (turns yellow at 10/75 skill level, green at 15/75, it's grey at 30, but it may have turned at 20 & I didn't notice )

The teaches tab here on Wowhead for Research: Ethereal Ink is actually incorrect in listing only one as I just now researched two glyphs:

Glyph of the Sha for Priest
Glyph of the Felguard for Warlock

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• The glyphs turn green at 37 or 38 (I'm 99.9% positive it was after 35 and before 40, but I wasn't paying attention, so I'm not positive which number it is. I know this sounds weird).
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The other things you can train from the bookcase are:
@ 5/75
Scroll of Strength VI (turns yellow at 15/75 skill level, green at 20/75 skill level, it's grey at 30, but it may have turned grey at 25 & I just didn't notice)
@ 10/75
Scroll of Agility VI (turns yellow at 20/75 skill level, green at 25/75 skill level, grey at 30/75)
@ 25/75
Darkflame Ink (also green when you train it, turns grey at 30/75)
Greater Darkmoon Card (turns yellow @ 50/75, green @ 65/75)
Book of Clever Tricks
Hellfire Tome

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• The offhand books both start orange, turn yellow at 40, green at 45, and grey at 50.
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In terms of skilling up, the scrolls can be useful while they are orange since they sometimes sell well on the AH, and you may be able to use them for leveling an alt. Additionally, not only do they take 1/3 the amount of ink of glyphs - 1 vs 3, they also have a higher vendor price than the glyphs: 2s1c vs 1s.

Unless these two glyphs sell particularly well on your AH, you may want to level up by grinding the research after 30 even though there's nothing to learn because the random things you get instead when you have nothing to learn may be more useful and actually sell better, especially since this occasionally procs as Enchanting Vellum. The Greater Darkmoon Card & offhand books are orange longer, but they require Darkflame Ink. The card needs half as much Darkflame Ink as the books, but it requires 3 Primal Life. It just seems easier to plan for leveling through research with Ethereal Ink, especially since you can use the ink trader to get it.

Sorry to be another bearer of bad news, in case anyone was looking forward to Outland Inscription! I am making these notes while doing Inscription a 4th time because it's so different from my first time back when it was released during Wrath. :)

This can be learned from [npc=33679] if you chose the Aldor

This can be learned at Shattrath at the Scryer's Tier; at 43.8, 90.4, inside the building you will find a number of clickable bookcases, each of which is named after a specific profession. Click the bookcase labeled "Inscription" and you will be able to interact with it as you would with a regular inscription trainer.