If you are doing photos only, I would skip ND filters. Blown out backgrounds give that "light and airy" look that a lot of people like, but at most venues, you can position people in front of trees or buildings. You can position for the sun to side light for photos.

To be honest, it's not going to be comfortable for your subjects to use a constant light bright enough to use in sunlight with an ND. If you do want to go with NDs, then flash is going to be the way to go.

For video if you are trying to stick to the 180 degree rule, then an ND filter would be helpful. Depending on your model camera, you can get one that sits between the camera sensor and the lens. I have this 6-stop one for my Sony 7iv: https://www.amazon.com/gp/product/B08FHK3N5M

I also have a Tilta Mirage Matte Box and I have the variable ND for that one, but that may be out of your budget: https://www.amazon.com/dp/B09GDHV7VR

I use that one on my video-only days.

If you are doing both photo and video for the same event, then you are going to have to compromise one or the other. You can try multiple cameras. I've done that once, not for a wedding. One camera handheld on a gimbal for video, and another on a camera strap for photo.