There are two ways:
While creating a 'New Video' - you can choose what type of visual style you would like the AI generated images to be in. Please scroll through the 'Image style' drop down to browse through all styling options.
2. Once the video is generated, you have full flexibility to change image style. To get started, click on the 'edit scene' button
That will open a popup - click on 'AI image' tab and select the visual style you would like to proceed with.
You can also add a custom prompt for the image if you would like to try out a different concept here.
That's it - easy peasy!