On 24 January, she participated in ''hololive 1st fes. Nonstop Story'', along with the other hololive girls up to the third generation, where she debuted her 3D idol outfit.
On 16 March, she reach 200,000 subscribers on her YouTube channel.
On 7 June, she reach 300,000 subscribers on her YouTube channel.
On 11 July, she announced on her Twitter account that she wasn't feeling well and that she couldn't stream. Later on 13 July, she specified that her condition had nothing to do with the COVID-19 pandemic.
For the following days, she didn't stream so that she could rest in preparation to perform with Hoshimachi Suisei at VILLS Virtual UNIT Fest on 19 July. After performing in said event, she also announced on her Twitter account that she would return to her streaming activities on 26 July. However, on that day, she announced that her return scheduled for this day would be postponed because of talks with the management team.
On 31 July, just a day away from her debut anniversary, Cover Corp's Twitter account announced that Miko would be on hiatus for one or two months to take treatment for and recover from her illness. She confirmed this shortly after on her Twitter account. Sadly, it went into an nearly-three-month hiatus, but her Twitter account was still active, with Miko posting in her normal basis and even creating a daily-like posts section, in which she wrote about her daily life with some small drawings she drew.
On 3 August, she reached 400,000 subscribers on her YouTube channel.
On 1 October, she reached 500,000 subscribers on her YouTube channel, making her the 14th in hololive and also the 2nd member in the 0th generation to reach the milestone.
On 17 October, she announced on her Twitter account that she would return to her activities on 21 October. On this date, she returned to her activities with a live 3D concert stream celebrating her second-year anniversary on YouTube. The stream was seen by an average of 128,426 live viewers and peaked at 145,305 live viewers at the 48-minute mark, making it the most watched hololive stream of the year in live viewership, and a record live viewership for a hololive stream up to that point.
On 7 November, she reached 600,000 subscribers on her YouTube channel during a stream of the game GTA V.
On 2 December, Miko debuted on Twitch; her Twitch channel would be used for movies "watch along."
On 8 December, she reached 700,000 subscribers on a singing endurance stream, being the 14th member of hololive to do so.
On 17 December, Miko announced on her Twitter account that her current 3D model would be updated to the 2.0 version.
On 21 December, Miko participated on stage 1 of ''hololive 2nd fes. Beyond the Stage''.
On 23 December, she revealed her new 3D model, with one of the most notorius changes being that in the new model, her eyes match the redesign Miko received in artworks in 2019 by her new designer, Ordan. Like those of others, to which underwear censorships to prevent potential YouTube bans were applied, her model was updated to wear a pink short under her skirt. Her original appearance model also received a face update.
On this date, Miko also debuted her third original song, "Sakurairo High Tension!" 「さくら色ハイテンション!」, and announced her own visual novel Sakurairo Dreamer 「さくら色Dreamer」.