The artist was Victor Guerrier. Various web sites credit those paintings to a Victor Guerrier whose dates are 1893-1968. But there seems to have been another French painter named Victor Guerrier who lived 1858-1953. There is essentially no biographical information about either man.
Given his dates and the Belle Époque settings, it would seem that the earlier Guerrier should have been the artist. The style of the signatures on the paintings hints at that as well. But if all those art auction, etc. websites state that the 1893-1968 Guerrier was the artist, then he would have to have concentrated on the Belle Époque as an artistic faux-sentimentalist, having been a boy in those times.
If anyone knows the truth about this puzzling matter, please let us know in Comments.
Here are some of those paintings.
This looks to be set just before or after the Great War.
By the Luxembourg grounds, the Panthéon in the background. I don't notice the McDonald's I sometimes visit that should be at the far right of the image.
Guerrier painted several flower shopping scenes.
Is that the Café de la Paix in the background?