This thread was originally about Men's Soccer, but here are some of the other effects on the MPSF due to the WAC/MWC realignment:
Women's Gymnastics - Denver will be the only full member of the post-football WAC that sponsors the sport, as San Jose State and Utah State move to the Mountain West. Boise State (Independent) and Air Force (MPSF) are the only current MW schools that sponsor the sport, meaning the MPSF likely goes to nine (Denver, Air Force, Southern Utah, Utah State, San Jose State, Sacramento State, UC Davis, Alaska Anchorage, Seattle Pacific). If any other MW schools start the sport, the MW could sponsor a championship, especially if independents Boise State and BYU are on board. The only 2 remaining Big 12 schools sponsoring the sport (Missouri is headed to the SEC) are Oklahoma and Iowa State, and Oklahoma already has its Men's Gymnastics program in the MPSF.
The Mountain West will have 4 of the 9 Men's Soccer members after Houston Baptist comes over from Atlantic Soccer. Atlantic Soccer could lose NJIT to America East, and will lose Longwood to the Big South. Remaining members Adelphi (NY) and Howard (Washington, DC) would probably join the MAC, which already has soccer-only members Florida Atlantic and Hartwick College, although the CAA could also be in play. Georgia State (leaving CAA for Sun Belt) could also be looking for a new soccer home.
In Men's Indoor Track, the Mountain West loses TCU and Boise State, but picks up Utah State to settle at five schools. This leaves the WAC with Boise State, Idaho, Seattle, and possible new members Cal State-Bakersfield, Utah Valley, and UTPA. There are a few western independents as well (Portland, Gonzaga, UC Riverside, and Loyola Marymount), so with a few partial members all 3 conferences could continue to sponsor the sport. If the Pac 12 ever starts offering a championship (9 of the 11 MPSF members), the MPSF could pick up all of the strays, or drop the sport.
A similar situation exists in Women's Indoor Track, although the WAC would also have NMSU, and the MPSF has one more member in UC Irvine. If the PAC 12 ever offered its own championship, a Big West championship in the sport would be more likely.