Right now a druid with Alert and in animal form that has keen senses can benifit from both, if you change it having double advantage doesn't do anything.
Now human level 2 druid 16 wis has a passive perception of 20 (25 involving whatever keen sense the animal form has).
10 +3 wis mod +2 prof +5(Alert) =20, and having advantage from keen senses gives another +5 to passive perception.
Now human level 2 druid 16 wis has a passive perception of 20 (25 involving whatever keen sense the animal form has).
10 +3 wis mod +2 prof +5(Alert) =20, and having advantage from keen senses gives another +5 to passive perception.