The plot area for a villager home has to be 3x3, with no rocks/buildings/PWPs in the 5x5 area surrounding, plus one space for in front of the door. From that picture, she should be able to plot there.
The way I get villagers to plot in certain areas is by putting patterns all over my town, leaving only 3x3 plot areas that I want villagers to go in. But, if your town is more developed, this is more difficult.
An extra note: Villager's will not move onto patterns with Welcome Amiibo, but they will move onto flowers and trees.