Probably not. Switching from one consumer APS-C system to another is unlikely to make a material difference in whether your stock images are saleable.

For stock photography, the bigger factors are usually:

• composition and subject choice
• lighting
• technique
• lens quality
• support gear like a sturdy tripod

A different APS-C sensor may give modest gains in dynamic range, noise, or sharpness, but those differences are small compared with the impact of strong shooting technique and better optics. Many excellent stock images have been made with cameras less capable than the 700D.

Before changing systems, it makes more sense to refine your workflow: use lower ISO when possible, stabilize the camera well, expose carefully, and consider techniques like bracketing or stacking when appropriate. If you specialize in a subject, targeted lenses may help more than a new body—for example, tilt-shift lenses for architecture or better telephoto glass for wildlife.

In short: don’t expect a Canon-to-Nikon APS-C switch alone to make your work saleable. Improve technique and invest in the lenses and support gear that fit the type of stock you want to shoot.