is there a way to make the thumbnails all the same size regardless of what dimensions each thumbnail is uploaded? Idealy I’d just upload them all at the same size but as I intend to have a lot of content this might not be very feasible and the masonry view on the blog and portfolio looks prety weird with everything at different sizes and shapes.
I forgot to mention this is also a problem for my list of products. I basically just want all the images to fill a set shape so they can be neat and tidy in columns
You are able to manage your product images size and enable hard crop to make them all look the same size in Appearance -> Customize -> WooCommerce -> Product images. You will also need to regenerate all thumbnails after changes.
As for other images, you can specify their sizes in Dashboard -> Settings -> Media. Unfortunately, there is no option to enable hard crop there for blog posts and portfolio.