Quote Originally Posted by Paulbot
Transmetal Waspinator would look at home with the Insecticons (and comes in two colours) or the original Waspinator and his repaint Buzzsaw.

Others that come to mind are Insecticon (beetle), Manterror (mantis), Powerpinch (earwig), Inferno (ant), Scavenger (robot ant), Cicadacon (cicada), Ramhorn (beetle)

There's also a scorpion and some spiders but I think those aren't technically insects.
Yeah, there are several arachnids in Beast Wars.

Other BW insects you left out were:
+ Jetstorm (dragonfly)
+ Retrax (pillbug)
+ Transquito (mosquito)
+ Drillbit (boll weevil)
+ Scarem (stag beetle, Transmetal 2)

From Japanese BW...
+ Big Mos (mosquito)
+ Powerhug (pill bug)
+ Tonbot (dragonfly)
+ Mantis (mantis)
+ Drill Nuts (boll weevil)
+ Scissorboy (earwig)
+ DJ (cicada)
+ Motorarm (dung beetle)
+ Dirgegun (cybernetic wasp)

Convention exclusives...
+ Antagony (ant
+ Vice Grip (earwig)

McDonald's Happy Meal toy...
+ Beetle (beetle)

And Digger I don't know if you'd be interested in half insect modes, but here are Fuzors with semi insectoid modes...
+ Buzzclaw (mantis, lizard)
+ Injector (hornet, lionfish)
+ Sky Shadow (dragonfly, iguana)

And from Blentrons (repaints of Fuzors but entirely different in TF canon)
+ Rartorarta (hornet, lionfish)
+ Drancron (dragonfly, iguana)

The Buzzclaw mould has also been repainted for Universe and Timelines (e.g.: Virulent clones) which are convention exclusives.