Hm..... There are a lot of items you could add, with the Japanese style.
If you aren't sure what it and isn't, why not watch some model makers?

https://www.youtube.com/@hms2-miniaturekobo2/playlists
This creator does a lot of fantastic models, and is excellent to watch for style

Personally, I love the kitchen and bathroom items.

And since Zomboid is so much like the sims 1.....
Here is a Japanese sims1 site to look at for items. I've had some cool things over the years from places like this lol.

http://gyoikosakura.jpn.org/main.html

●雨戸(amado) - storm door
https://external-content.duckduckgo.com/iu/?u=http%3A%2F%2Fgotenba-furusawa.madoshop.jp%2Ffcontents%2Fimagenew%2Fshop%2F75%2Fshop_jirei%2Fcache%2F13%2F768x768%2F%25E7%258E%2584%25E9%2596%25A2%25E5%2581%25B4.jpg&f=1&nofb=1&ipt=4be5308c9ac632d59b52328505e68722be8b8c701c3f0a89638baaf6c83ad309&ipo=images
A sliding door made of wood to protect the shouji.
I understand that this mod does not emphasize reality.
However, there is a limit to how much you can keep out the rain with just shoji.
I think that the colors and architecture will be sharp.
amado is a simple door made of wood and nails.


●襖(fusuma) - fusuma
https://external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fkanazawaya-yumigahama.jp%2Fcommon%2Fupload_data%2Fkanazawaya-yumigahamajp%2Fimage%2F20191008185915.jpg&f=1&nofb=1&ipt=02618106957e1f9b917ec28c94e6132d85098cd2b7e77539c22e3384a8c59763&ipo=images
Fusuma is a wood-framed sliding door and partition covered with thick paper.
It is movable in grooves and separates the rooms of Japanese house.
The fusuma paper bears a variety of patterns.
Plain white fusuma is also often used, but it might be interesting to have other patterns as well.
Japananese paper for shoji is thin and translucent.
By the contrast, fusuma is made of thick paper.
Materials are glue, paper, and wood.


●座布団(zabuton) - Japanese cushion
https://external-content.duckduckgo.com/iu/?u=https%3A%2F%2Ftmbi-joho.com%2Fwp-content%2Fuploads%2F2016%2F11%2F%25E5%25BA%25A7%25E5%25B8%2583%25E5%259B%25A3.jpg&f=1&nofb=1&ipt=8ce52e8fe16e18af30b2988515270380014335f67102fea73a27838966d590cf&ipo=images
A chair used in a Japanese-style room.
Many people use it as a pillow when sleeping under a kotatsu.
Green and indigo are common colors, but colorful patterns are becoming more popular nowadays.
Need material is cloth and cotton.


●こたつ(kotatsu) - Japanese foot warmer
In your mod, it looks more like a horigotatsu.
掘りごたつ(horigotatsu) is a type of kotatsu with a low table floor.
https://external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fwww.sankouhome.jp%2Fwp-content%2Fuploads%2F2013%2F10%2FDSCN6551.JPG&f=1&nofb=1&ipt=c14b4907c9943bd9f5788793bbfb8421d435077f2b9802b8364105948056278a&ipo=images
A normal kotatsu is made by covering the table with a thick cloth and placing a wooden board on top of it.
I would be happy if you could add this type of texture.
https://external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fcdn.amanaimages.com%2Fpreview640%2F10170000178.jpg&f=1&nofb=1&ipt=50749387ca66604fe07afacbb6e5113d1eacc8cb2d540e910f2043794bd50d10&ipo=images


●ちゃぶ台(chabudai) - Japanese low table
https://external-content.duckduckgo.com/iu/?u=https%3A%2F%2Fsakamoto-kagu.up.seesaa.net%2Fimage%2F1000-2-1.jpg&f=1&nofb=1&ipt=50dd1edb9574a665d88326be203556a067837e7b51cf804036c253921dd9ff2d&ipo=images
A dining table with four legs used in Japan. They are generally square or circular, and many of them can be folded.
I felt that there was no circular one, so I told you.
It can be crafted from wood and nails or screws.
(ノ・Д・)ノ彡┻━┻

●神棚(kamidana) - household Shinto altar
https://external-content.duckduckgo.com/iu/?u=https%3A%2F%2Flivedoor.blogimg.jp%2Fyorozu_co_jp%2Fimgs%2Fa%2F3%2Fa3905b3f.jpg&f=1&nofb=1&ipt=420b75d741d140805f0de319d850750007c6e641f53520350a712d98aa6eb89b&ipo=images
A wall-mounted shelf for enshrining gods in Shinto.
Japanese people often claim to be non-religious, but in reality they have such religious furniture in their homes.
It should be above your head, in the cleanest, brightest part of the house, and in the south or east.
If you actually make a Japanese house, I think that if you put this kind of furniture, it will bring out a lot of atmosphere.
Is the material plates, bottles and cans, wood and tree branches?
I've never imagined building a Shinto altar in the post-apocalyptic world, so I might be wrong.

It's a great mod. I will let my friends use it next time. Thanks for making it public

@DarkServer Thanks for detailed suggestions!