Simmons was used sparingly as a freshman at Alabama, but was expected to compete for a larger role this year following the departures of ArDarius Stewart, Gehrig Dieter, and tight end O.J. Howard. The three of them accounted for 114 catches last year.
Simmons, who didn't previously announce his intention to leave the Tide, was also a standout performer in Alabama's spring game, hauling in six receptions for 82 yards and a touchdown.
The 6-foot-2 Pinson, Ala., native will take three seasons of eligibility with him to the Mountaineers, but will sit out the 2017 campaign to fulfill NCAA requirements for undergraduate transfers.
A former three-star prospect, Simmons was recruited relatively lightly in high school, with Alabama and Mississippi State being the only Power 5 programs to offer him a scholarship.