Bugs and fish

From OoT Randomizer Wiki

Bug Locations:
Death Mountain Trail - under rock next to Fairy Fountain (child only)
Desert Colossus - under rock near oasis
Gerudo Valley - under rock near entrance (child only)
Goron City - under rock in boulder maze
Graveyard - under rock near entrance
Kakariko Village - under rock, behind House of Skulltula
Lost Woods - under bush, outside of Goron City exit (child only)
Lost Woods - under bush, 2nd to last intersection before Sacred Meadow (child only)
Hylia Lake - under bush near scarecrows (child only)
Hyrule Castle - under rock behind tree right near Castle Town (child only)
Zora’s River - under bush on top of pillar leading to HP
Grotto's - Under bushes

Fish Locations:
Grottos (all contain bugs also):
Death Mountain Crater
Death Mountain Trail - outside Goron City (Song of Storms needed)
Hyrule Field - near group of trees in eastern part of field
Hyrule Field - outside of Market
Hyrule Field - outside Lake Hylia near tree
Kakariko Village - behind Potion Shop
Kokiri Forest - Gossip Stone outside Lost Woods entrance (Song of Storms needed)
Lost Woods - outside Goron City
Zora’s River - climb ladder
Zora’s Domain (child only)