You need one baseline in webflow. Either going horizontally or vertically.
As far as I know, this is the only two options you have with webflow.
Option 1 is the easiest. its just one dynamic list with images that adjust in width depending on how big they are.
This is ok if you are the one updating the site, but for a client its can be messy. Say you want it for a portfolio and you want to rearrange the images. You would have to do that with numbers.
Option 2 is a workaround for a masonry grid. With column a different dynamic list. This gets even messier if you want to re arrange the images.
It is kind of ironic, but webflow is not a great tool for building portfolios For my photography I use squarespace because of this lack of ability. And to all my photography, makeup, hair, styling and film friends, its squarespace.
Hopefully webflow will start using CSS Grid soon so we can make dynamic grids like the ones you want