I stand in the East, facing West in all directions
A day’s sail, just across the line
This must refer to
somewhere as far east as it's possible to go according to time zones, i.e. somewhere just on the left-hand side of the International Date Line. Sailing just across the line would mean changing time zone by around 24 hours, hence "a day's sail".
Possibilities at this stage are
Tonga, Samoa, Line Islands, Chatham Islands, ... maybe New Zealand if we're being a bit less literal?
Unlucky year, a ship ran aground...
So we're probably looking for
a shipwreck in a year like 1713/1813/1913/2013. Samoa has a bunch of shipwrecks but not in those years; Tonga has the Tongan castaways shipwrecked in 1965; the Chatham Islands also have a bunch of shipwrecks; and the Line Islands have also had shipwrecks, including one after which an atoll is named.
There's also
the Fiji shipwreck - in Australia, but the ship was called Fiji, and Fiji is near the International Date Line too.
Another approach:
we could look for shipwrecks in 2013 or 1913 or 1813, but none of them look very promising. The only ones I found in the right kind of location were small incidents in Alaska, nothing well-known.
Except ...
the Amaranth, a barquentine wrecked on Jarvis Island in 1913.
It fits the title of the riddle ("shrubby barquentine"), the unlucky year, and the location. So then the location we're looking for is
Jarvis Island, sharing a name with this character. Fitting the clued "n" in the name we're looking for, it's probably Tony Stark, which would also fit with the "elemental alias" of Iron Man. (Thanks @Stiv for this last connection!)
The only things I don't yet get are "blunt talk", "different world, different age, set the stage", and the image. But maybe these things would make more sense with some specific popular culture knowledge that I lack. Anyway, it seems that the final answer is
TONY STARK.
OP edit:
The island you were looking for is called Kiribati. Standing here in the Eastern Hemisphere, you see the Western Hemisphere in all directions:
Zooming in to the island, we see something that looks like the backwards 'h'. Note Paris and London at the legs:
Align the backwards 'h' to the map and follow the arrow (not too far, because it's only a day's ride) to meet Jarvis Island, the final resting place of the Amaranth Barquentine.
"A different world, different age Set the stage" refers to the answer not being of history, but instead fiction.
The word "Blunt" in the title is a synonym for "Stark".
