When comparing Canon EF 200mm f/2.8L II USM and Canon 7-63mm T2.6, which one is better?
The lenses each feature different lens mounts — the Canon 7-63mm T2.6 features a Arri PL Mount while the Canon EF 200mm f/2.8L II USM features a Canon EF — and because of this the preference varies. If you have a compatible camera, then of course that lens will be a better choice for you.
Winner: Tied — It depends on your gear
Regarding lens mount: Popular lens mounts are Canon RF and EF, Micro Four Thirds and Nikon Z. Different lens mounts lets you connect different lenses to camera bodies, but some might not be compatible. This can be helped by using an adapter, like a Canon EF to RF adapter.
The Canon 7-63mm T2.6 has the largest aperture of the two lenses at 2.6 compared to the 2.8 aperture of Canon EF 200mm f/2.8L II USM. This means that you get more light to your sensor using Canon 7-63mm T2.6 wide open, and therefore it might be a better lens in dark situations.
Winner: Canon 7-63mm T2.6
Regarding largest aperture: A lower aperture number means that the widest aperture on the lens is larger. This means that more light will hit the sensor and also that the depth of field will be shallower, better separating your subject from the background.
The Canon 7-63mm T2.6 is a Zoom lens while the Canon EF 200mm f/2.8L II USM is a Prime lens. Whether or not a zoom lens or a prime lens is what you need, is up to you to decide; they both have their respective strengths and weaknesses.
Winner: Tied — It depends on your gear
Regarding type: There are two types of lenses; zoom lenses and prime lenses. Prime lenses have a fixed focal length and cannot be zoomed, while zoom lenses have a focal length range and can be zoomed in to get closer to the subject. Prime lenses are usually lighter, cheaper and let in more light. Zoom lenses are more versatile but are more expensive since they require a more advanced lens design.
Full specifications table of Canon 7-63mm T2.6 and Canon EF 200mm f/2.8L II USM:
| Canon 7-63mm T2.6 | Canon EF 200mm f/2.8L II USM | |
 |  | |
| Brand | Canon | Canon |
| Weight | 1980 g | Missing |
| Lens Mount | Arri PL Mount | Canon EF |
| Focal Length | 7 - 63 mm | 200 mm |
| Largest Aperture | 2.6 | 2.8 |
| Anamorphic | Missing | No |
| Minimum Focus Distance | 60 cm | Missing |
| Type | Zoom | Prime |
| Aperture Range | 2.6 - 22 | Missing |
| Lens Front Diameter (Not Filter Thread) | 95 mm | Missing |
| Image Stabilization | Missing | No |
| Autofocus | Missing | Evet |
| Weather Seal | Missing | Yes |
| Full Frame Coverage | Missing | Yes |
| Lens Hood Included | Missing | Yes |
