On March 14th, the IHA released a 61 minute video titled "A Year in the Lives of Their Majesties: Ahead of His Majestys Abdication"
You can watch it for free on the government TV website.
English:
https://nettv.gov-online.go.jp/eng/prg/prg6207.html
Most of the footage covers official duties in 2018 and some private activities. Some screenshots:
Sayako!
Research
2017 year-end family lunch. Princesses Yoko and Akiko at the table behind Princess Kiko. Behind them, I think that's Princess Hisako, Sayako... and possibly CP Masako's father Hisashi Owada and Takako Shimazu (ex-Princess Suga, Emperor Akihito's youngest sister)
Making mochi flower trees in late 2017 for New Year 2018. You can see the trees in the first 2 photos above.