Fisher spent 13 years coaching for Penn State men's hockey.
"Penn State enters this new era of college sports in a position of strength and ready to attack this new collegiate landscape."
Rehfuss reunites with head coach Kayla Treanor after serving as her offensive coordinator at Syracuse in 2024.
Ott will be the only head coach in the NBA with ties to Penn State.
The Nittany Lions will look to win their fourth straight AHA Championship.
Johnson will join Kieger's coaching staff after being an assistant coach at the University of Miami.