5 letter words:
fixer15,
refix15,
mirex14,
mixer14,
remex14,
remix14,
fermi10,
4 letter words:
feme9,
firm9,
fere7,
fire7,
free7,
reef7,
reif7,
rife7,
emir6,
mere6,
mire6,
rime6,
3 letter words:
fix13,
mix12,
rex10,
fem8,
fee6,
fer6,
fie6,
fir6,
ref6,
rif6,
eme5,
mir5,
rem5,
rim5,
ere3,
ire3,
ree3,
rei3,
2 letter words:
ex9,
xi9,
ef5,
fe5,
if5,
em4,
me4,
mi4,
er2,
re2,