With the Chinese DLC coming in 2026, I expect there will be one or two, or even more, changes to China and Zhu Xi’s Legacy.
Chinese Campaign
Judging by the promotional image for the campaign, which features a Song Dynasty general, I assume it will include several battles against the Khitans and Jurchens.
Considering that Age of Empires II: DE already includes ““Jurchens”” and “Khitans”, with their own bonuses and unique units, including the Iron Pagoda cavalry, I hope that if they appear in the Chinese campaign, they will be well represented.
At least with Sultan Ascend, they created new units for the Templars campaign (The Beast, Genoese Crossbowman, Templar Knight, Teutonic Knight, Hospitaller Knight) and some for the Ayyubid (Turkish Horse Archer, Dervish, Manjaniq), so I expect the same for the Chinese campaign.
Maybe, with the new units models, could be space for a future Khitan or Jurchens civs, or Korean, Vietnamese, etc.
Bed Crossbow or Siege Crossbow for Chinese
Considering that some levels of the campaign will take place during the Tang or Song dynasty, it would be good to consider a siege weapon more suited to that era.
The Bed Crossbow was a siege crossbow that, like Western ballistae, was used to fire at guards on walls or towers, or from high positions and fortifications to fire at attackers.
Currently, it is a special siege unit for the Chinese, present in Age of Mythology for the Chinese civilization.
The Japanese in that game also have another variant of the Bed Crossbow, called the Oyumi.
In AoE4, the Bed Crossbow would be the East Asian version of the Springald, currently for three main civilizations: China, Mongols, and Japanese.
It would also appear in the two variants: Zhuxi and Sengoku.
Future civilizations, such as the Jurchen, Khitan, Vietnamese, and Khmer, would also have this model.
It is important to consider this model because a unique unit, the Khmer Tower Elephant, had this type of crossbow mounted, unlike the Western version.
New Naval Units:
Many Chinese naval battles of the Song and Tang dynasties featured the use of unique ships.
One of these is the Low Chan, a warship with a traction trebushet. This unit is already present in Age of Empires 2 for China and for the Three Kingdoms variants.
In Age of Empires 4, there is another unit with a counterweight trebushet, the Venetian Galley for Templars. It could very well function similarly, but with a shorter range (traction trebushet).
On the other hand, they could also consider that Age of Empires 2 planned a remake of its naval system, and now they will have melee warships. This idea should be seriously considered for Age of Empires 4, at least as a replacement for the explosive ship for Feudalism, making it more situational. This would at least make naval battles longer and more interesting.