To avoid print supports on a box-shaped object, tilt your object 45º in your modeling software and position it on this stand.
Align your object so that the teeth of the stand are about 0.2mm into the body of your object.
Export your model with the stand together as an STL or STEP file for printing.
You can now print without supports, and if you position it right, the stand should break away easily from your model, leaving only minor marks where the teeth were. You can file or sand those or use fuzzy skin to ignore them.
This was inspired by this YouTube video: The Correct Orientation to Print Boxes
I was looking for an example of a print stand like this but couldn't find one, so I thought it might be useful to you, too.
Actually, they call them support fins in the video, and I only saw after I made this that they have some for sale in the YouTube comments, so that's an option too.
Here's a direct link to the OnShape model.
I used this stand recently on a Multiboard Gridfinity Chest Drawer remix.
The author marked this model as their own original creation.