That is true, I'm glad to hear that you are open to this different kind of AoE (Elrond, Dwalin like) on different classes nonetheless
Taking into account your feedback, I came down to the following reflection. This ability fits the best for Warriors of the east and south and also Dwarven class.
The 'factions' that the Warriors of the east and south represent are based on asian culture, so much to the point that the Easterling warriors can be easily noted to be a version of the samurai and the Hasharii can be identified as a version of a ninja. In such regard, asian cultures have/had highly skilled martial arts warriors, which notably includes fighting several attackers at once. (
https://www.youtube.com/watch?v=4Aal7cB5ssQ , note the first full minute as Eg). Doing the adaptation to the game, this can be translated to an AoE attack. Last but not least, this class ONLY has "Plague of Locusts" as an AoE, and it frankly doesn't do much; they could use a new AoE ability.
Maybe this could be a fitting icon for them:
https://www.google.cl/imgres?imgurl=http%3A%2F%2Fvignette1.wikia.nocookie.net%2Fdynastywarriors%2Fimages%2Fa%2Fae%2FTwin_Swords_Weapon_Skin_(DW7E_DLC).jpg%2Frevision%2Flatest%3Fcb%5Cx3d20130110202615&imgrefurl=http%3A%2F%2Fkeywordsuggest.org%2Fgallery%2F848118.html&docid=EoTsxN37NCQWnM&tbnid=Y4DdM_AwEt5dXM%3A&vet=1&w=1280&h=832&bih=530&biw=1093&ved=0ahUKEwiM6u6pk_jUAhUFi5AKHaZgAP4QxiAIGigC&iact=c&ictx=1Now for the dwarves it goes different. Historically, dwarves have notably fought throughout the third age battles in which they are greatly outnumbered; take The Battle of Azanulbizar as an example, 6-10 thousand dwarves against 25-30 thousand orcs, or the siege of Erebor where 30,000 Longbeards and 20,000 Men of Dale held the Lonely Mountain against 200,000 Men of Rhun. Now call me crazy but being so greatly outnumbered implies the skill to fight more than 1 opponent at once, (excluding the strategic position of the Lonely Mountain on case 2, but either way the dwarves are best known for melee combat, not ranged). Take Dwalin or Gloin as an example in this scene, both Azanulbizar veterans
https://www.youtube.com/watch?v=IccbfvmsgTI .
Last but not least, the dwarven Wanderer is notably the only CaH capable of carrying 2 weapons at once, it is only natural to put them into use via the purchase of this ability. (the second axe item is actually bugged right now btw but you get the point).
Possible icon:
https://dhs1n389ze6jv.cloudfront.net/img/product-main/87-39-00987_Hobbit_Dwalins_Axes_002.jpgSorry if this extended too much but you guys deserve a well grounded argumentation, hope you like the idea