Fukushu no Mibojin (2022)

Suzuki Mitsu is a talented contract engineer working for an IT company, but it wasn't their benefits package that attracted her. She's working for the company that drove her late husband to suicide, and she won't rest until she exacts her revenge on each and every person responsible.

Hino Misaki, a full-time housewife, has given up on her dream of being a manga artist. Her husband, Toru, is a manga editor, and their son, Yuto, has a severe allergy. When she sees a flyer recruiting new manga artists, Misaki begins drawing at night. One day, after leaving Toru to watch over Yuto, Yuto dies after a severe allergic reaction. After the funeral, Misaki learns that Yuto died due to an allergy attack from muffins from Toru's affair partner. A woman who wished for small happiness, but after realizing her wish would not come true, chose the path of revenge

Both have similar theme. In both the series FL has hidden identity and seek revenge.
Will update soon.

Both have similar vibes about revenge though the premises are different.
Black revenge deals with scandals and in media however Fukushuu no Miboujin is setup in corporate IT Company office.
Both are good to watch.