okay I have not followed Ebberon through the editions and I really only steal stuff for my homebrew... so forgive me but...
is it any harder to train a magewright then it is to train a battlefield engineer? I was under the impression (and I may be wrong) anyone CAN learn magic since at least 4e, if not 3e... the inborn spark went to sorcerer and now wizards and artificers (and magewrights) could be anyone with a 12+ intelligence.
it depends on what
kind of magewright. Think of it like the arcane equivalent of "
tradesman" & doesn't by itself mandate an extreme level of skill. While
@doctorbadwolf is doing his best to make it sound as if every single magewright has a multiyear degree from the arcanix or something, but that is very much not the case in eberron & it includes a good number of jobs we would consider low skill or barely skilled like lamplighter & launderer as keith has
written about before.
Elsewhere he's written things like
"In Aundair, a farm might have a floating disk that serves some of the same purposes as a tractor. In the Eldeen, you might have gleaners – the druidic equivalent of magewrights, with farmers knowing a simple druidic ritual or two to help with the crop.".
I'm not sure if there is significant difference between "battlefield engineer" & "
combat engineer" but I think they are probably just different terms for the same general thing & will assume as much. A magewright who joins the military might be assigned to a unit with a similar role nto those & receive specialized training for the role that particular unit exists for (ie bridgemakers rarely have much to do with building irrigation systems & power grids). Using that bridgemakers/irrigation system/power grid split where different units might be specialized for those specific things they all likely have enough combined skills to put a temporary solution in place till some specialist could be assigned or hired to do it right. That's not to say every magewright would be assigned to a unit where their skills as a magewright are all that relevant to what they do, only so many lamplighters seamstresses masons launderers & anything else are needed in those roles. Some of the artificer archtypes are basically extremely skilled & ihighly trained combat magewrights too but those aren't the norm.
@doctorbadwolf yes aundair has much more magic than most of the other nations, but they have that
because the queen of aundair invested in the local resource at her nation's disposal known as
the arcanix/the arcane congress. Karrnath has a lot more undead than anyone else
because having a local resource known as the mabar manifest zone made that sort of investment a good one for them. It's not a situation like FR where you have an advanced mageocracy next to a bunch of leaderless dirt farmers beside a technologically advanced hermit nation overlooking maurading bands of savage raiders who do nothing but go around plundering.
You also miss the point of why
"the cannon could be replicate by a kingdoms own people, no need to be beholden to Cannith for it." would be equivalent of severing ties with Cannith. Nobody is physically capable of engaging in the sort of manufacturing cannith is at a similar cost & scale because doing that requires one to bear a mark of making just to use the dragonmark focus items that make it possible. Cannith has facilities all over & are thrilled to take their cut from selling things that
enable people lacking a dragonmark. Those people are thrilled to give that cut too because it's either not possible or too expensive to do it in a way that cuts cannith out