You can look at the recruitment of additional races for the horde (beyond the original Orcs, Tauren and Trolls) as a means of plugging gaps in the Orcish system of warfare.
The original Orcs of Draenor (MU, appears lesser for AU) were afraid of open seas. A combination of auspicious beliefs about the ocean spirits and the fact that the ogres came from across the seas meant orcs never had any interest in sailing historically.
This is fine. Until you find yourself embroiled in a war with a faction that boasts seafaring capacity, enabling them to transport hundreds of troops and equipment of weight, far more reliably and efficiently than a zeppelin can at least. At this point the fact the Orcs lacked proper designs for their own ships and relied overwhelmingly on Ogre shipbuilding, which was no longer a feature of the horde since the ogres left.
When you look at it this way, introducing the Forsaken and Blood Elves, whom both have some naval resources and knowledge seems sensible. More so for Goblins, whom are renowned for piracy and seafaring. The Zandalari are the cherry on the cake.
The Magâhar bring their Dreadnoughts. These still in a distant manner come from non-orcish sources when you consider the imposition of the Iron Star in the AU. Additionally the Dreadnought design appears heavily influenced by Ogre juggernauts.
So really, even now, MU Orcs still donât build ships. Itâs the one part of warfare the Orcs seem to leave to their allies. Youâll have Orcish captains and crews (though examples are not massively numerous, and often shown to be somewhat amateurish and more akjn to pirates a la Silverpine).
So essentially this tidbit is, MU orcs probably still have a bit of a wierd relationship with the sea. Older orcs who saw Draenors sundering will probably still be quite wary of the sea itself. Up until this point in the MU itâs reported that the Orcs stayed away from the sea, unlike their AU counterparts.
