Envisage - envision
The OED records the earliest use of envision as in 1921. Its meaning is given as including the word envisage: To see or foresee as in a vision; to envisage; to visualize. To envisage, which has a larger set of meanings, only dates back to 1820. So it is not an ancient word.
Nevertheless, the word envision seems to be entirely unnecessary. Avoid it. Use envisage instead. Fowler suggests that envision is much more common in American English, envisage in British. That seems to a British academic like me a good reason to reinforce my advice.