Other mistake: The beginning of Annabelle Comes Home claims to be in 1968. That is the year the Warrens acquire the Annabelle doll. However, the original Annabelle movie depicts the pregnant character getting Annabelle as a gift from her husband, and near the end of the movie Annabelle is in a pawn store where a mom mentions buying the doll for her daughter who's a nurse. That nurse is who gives Ed and Lorraine Warren Annabelle. So, going back to the beginning of the original Annabelle, when Annabelle Higgena and her boyfriend attack the parents and neighbour a news reel shows with a newspaper depicting "October 3rd, 1970." Baby is born, time passes, bringing the movie to 1971. Therefore Annabelle would not have "come home" until 1971, even 1972 depending on how long the nurses had her for - not 1968. This throws a wrench into the entire Conjuring/Annabelle line of movies. When you take that into account the rest of the movie dates do not add up.
Other mistake: The movie is said to be set one year after receiving Annabelle, but the music box from The Conjuring is on the shelf. Judy in The Conjuring is an 8, possibly 9 year old whereas in this film she celebrates her 10th birthday. If Annabelle Comes Home" is only 1 year after obtaining the doll (2 years prior to The Conjuring timeline) then Judy would not be turning 10 years old; she essentially lost a few years of life rather than vice versa.