Let's get going.
The Pokemon duplication glitch (aka cloning glitch)
The regular duplication glitches was available in every Generation but V, which means that the duplication glitch isn't possible in B2/W2. However, there are other ways to perform the duplication glitch in Gen V, which are listed on this article:
- By abusing trading. If the player turns off the DS at the correct time, the original trainer AND the trainer that receives the Pokemon will have the same Pokemon. It is confirmed this is successful in Gen IV (I've done it myself too), but is apparently uncomfired if it is successful in Gen V.
- By abusing DNS addresses.
In Generations IV and V, by manually specifying the DNS address so as to connect to a server other than the GTS, it is possible to clone Pokémon.
The glitch that allows you to go to Sinnoh
Never heard of this one. Nothing seems to have information about the glitch; and besides, the game doesn't have ANY way of accessing Sinnoh programmed. This glitch doesn't exist, and to access Sinnoh in Gen V, the player must have HACKED the game.
The MissingNo. glitch
OK, to put this straight: the MissingNo. glitch can only be performed with the old man glitch (R/B) and the Mew glitch (R/B/Y), which are not performable in Gen II - V. So that's another glitch un-performable in Gen V.
The 99 Rare Candy glitch
No such thing. Again, you can get 99 Rare Candies by hacking, but no glitch allows this. However, there was a glitch in Gen I that allowed you to duplicate items, where the Rare Candy was a popular choice to duplicate. The glitch is explained here, but it is not possible in Gen II - V.
Tweaking (or the void glitch)
Ah, interesting :)
Again, this hasn't been confirmed possible in Gen V, but was possible in IV (as seen here). It is likely not possible, as Game Freak seem to have removed the 32-step by 32-step squares rule, which means tweaking wouldn't be possible in Gen V. But nothing is confirmed, but currently there is no method that allows tweaking.

The egg thing
Again, not a glitch, but a hack. Probably possible with various cheat codes from things like Action Replay, but without them, the only thing that relates to this is the Bad Egg, which hatches into a glitch Pokemon called '-----'.
So basically these are all hacks, and the ones that ARE glitches are only possible in the older games (mostly Gen I, which was extremely buggy).
More info:
http://bulbapedia.bulbagarden.net/wiki/Glitch
http://bulbapedia.bulbagarden.net/wiki/List_of_glitches_in_Generation_V