The film is Oracle, a 2007 animated short from France, directed by Sébastien Buisson, Michael Desnoyelles, Tristan Le Granché, and Flavien Lens, with music by Mylcis.
The film's poster shows what looks a test tube and a fidget spinner. The spinner also appears in the title sequence:
Around ten years ago
The film was released in late 2007 and made the festival rounds in 2007 and 2008. The film had a website; however, whatever is currently at the film's domain gets flagged as malware, so don't try to visit it directly. The content from 2008 is mostly navigable at the Internet Archive as is a review on Sci-Fi Universe.
I saw a short film
This film is just under 8 minutes long.
The film is still available on YouTube.
a parent taking their child to a machine which would then simulate their future. The future the machine simulated for the child started out with her playing around in a grass field. As she played, flowers would sprout and small animals would appear that she would also play with.
This film starts with a dad being spoken to by a disembodied voice. There is a little dialogue at the beginning, but I don't speak French and this upload doesn't have subtitles.
I think it's saying something like "What parent wouldn't want to know their child's future? (something something) ... the choice ..."
Then a baby appears, and some waving grass, and the baby starts bouncing through the grass, and flowers appear:
After the baby scenes, there are scenes of a young preadolescent child touching the ground and flowers and trees appearing:
In the mid teens the simulation took a darker turn. She found a black vine in a canyon, which she then touched. I don't remember if touching it changed something about her physically or just made what she touched sprout the black vine.
When she is 16, she is wandering through a canyon full of strange plants and happens across a spiny cactus-looking thing.
After she touches it, it sprouts black viny runners:
She defiantly slaps her hand on the canyon wall and allows the vine to take her over:
When the vine recedes, we see that she has been transformed:
The last scene of the simulation i think was her at a podium giving a speech while clad in dark colors while below her marched endless ranks of people in uniform.
She summons or generates an army of marching soldiers and stands before them, not on a podium, but on an outcropping of rock:
The film ended with the machine stating something along the lines that the child has high levels of aggression and asked whether the parent wanted to keep the child and then the parent making the choice to keep the child.
After the simulation, the dad is breathless and concerned. The disembodied voice speaks to him (in French), and there are two buttons before him: Accepter (red) and Refuser (green). He takes a deep breath and slaps the Accepter button:
A pod comes out and opens to reveal his baby:
I believe the film was called "Oracle" but I haven't been able to find it. I think the film was not in English and I was watching with subtitles. Around the same time I also saw "Sintel", so it might also have been made in Blender.
Correct on the title, correct that it's not in English.