Orbeetle is an interesting take on the 3 stage early bug evolution line. It spends a very long time in its cocoon as a Dottler, not that most trainers would complain as having a cocoon that armors itself and teammates by throwing up Screens is quite the boon on any team.
However, Orbeetle falls short on the competitive scale. This is not a good generation to be part Psychic type. Knock Off is everywhere, the superstar new Psuedolegend is part Ghost and U-Turn is as common as ever. Bug does not do Psychic any favors, just adding its Flying, Fire and Rock weaknesses (well, Psychic does not do Bug any favors), along side resistances to Grass, Ground and a redundant resistance to Fighting. Its stat distribution isn't that bad, its typing being the main letdown for its good defenses. Base 90 Speed is actually fairly fast for a defensive pokémon, but is still outsped by several crucial targets, and Base 80 SATK being below average, but still usable. However, it has 0 answers for Steel types, and its passivity can turn it into setup fodder. Orbeetle has a lot of fun tricks, but it can just as easily backfire on you.
Invasion of the Bug Snatchers
Orbeetle
Ability: Swarm
Item: Weakness Policy
-Agility
-Stored Power
-Bug Buzz
-Hypnosis/Recover
Nature: Timid (+SPE, -ATK)
EVs: 4 DEF / 252 SATK / 252 SPE
Weakness Policy Stored Power set. Take advantage of Orbeetle's many weaknesses and great bulk and to proc the Weakness Policy boost and Orbeetle becomes a threatening sweeper. Agility turns the Weakness Policy boost into a Shell Smash without the defense drop and jacks Stored Power up to an obscene Base 140 STAB move. Bug Buzz threatens the many Psychic and Dark types who blank Stored Power. Last move is up to preference. Hypnosis enables Orbeetle to shutdown a counter, or at least disable it long enough for Orbeetle to tear it to pieces. Recover gives Orbeetle longevity, enabling it to take more moves and so it does not have to worry about being KO'd by a priority move.
However, this set still falls short on several accounts. Steel types wall this set, though admittedly they are usually 2-3HKOd, as is anything that is especially tanky on the special side (Goodra, Chansey, Assault Vest). Orbeetle's base 80 SATK is especially evident in missing the OHKO on many Bug weak Pokémon like Umbreon, Cresselia, and many Stored Power resistant targets. After an Agility, you are still outspeed by Scarf Dragapult (but only that -Timid Regieleki is still outsped)
P.S. Hide your Miltanks and Tauroses (Taurosi?)