Autumn leaves in mountains near Tokyo?

Could anyone point me to good websites / blogs / facebook or instagram pages etc showing the state of autumn leaves in the mountains around Tokyo? I'm thinking about Mt Takao, Mt Mitake, Tanzawa-Oyama, Nikko and Kawaguchiko. I'm hoping to travel to Japan in the autumn of 2022, if Japan is open to tourists by then. I'm aware that peak color will be earlier in the mountains than in the city, so I'm just trying to work out if I can do both! Thank you.

I am not aware of many places specific to the exact spots that you mention, but there are a number of sites for the koyo season in the region, or nationwide. And it is a lot more even-tempered than chasing the cherry blossoms.
You could look at:
https://www.kyuhoshi.com/japan-autumn-foliage-forecast/
https://tenki.jp/kouyou/ranking/
https://www.jalan.net/theme/koyo/ranking/shutoken/
http://www.nihon-kankou.or.jp.e.wp.hp.transer.com/kouyou/
https://weathernews.jp/s/koyo/area/kanto.html
https://koyo.walkerplus.com/list/ar0300/
https://kids.rurubu.jp/article/41006/

That will give you info on at least part of what you mention, as well as many other popular places. If you can't read the Japanese on some of them, you'll need to run the site through a machine translator.

Here on Japan Guide, if you go to the three bars on the right hand side and click.
Then click on eInterestsf.
Then click on eBy Seasonf.
Then finally click on eAutumn Colors.

This will get you to the Autumn Fall Colors page on Japan Guide. There is a button on this page for eReportsf. There are no reports for 2021, but there are reports going back the previous 13 years.

There is one for October 27th, 2020, saying that Mount Fuji was at peak color. I believe that this is what you are looking for. Every year is slightly different, so I would suggest going back several years, to get an overall feel, and not use just one report.

Good luck, in planning your vacation.