No. Pokemon Omega Ruby and Alpha Saphire are remakes of Ruby and Sapphire, from 3rd Gen. Omega Ruby and Alpha Sapphire are in the same generation as X and Y, 6. Hope this helps you.^w^
Yes, all the TMs that were in Pokemon X and Y will be available as TMs in Pokemon Omega Ruby and Alpha Sapphire.
There are some Kalos region pokemon available in Omega Ruby and Alpha Sapphire such as Skrelp and Clauncher. More are available in Pokemon X and Y.
Inkay is unobtainable in the games before X, Y, Alpha Sapphire, and Omega Ruby.
After you complete the Primal Kyogre or Primal Groudon narrative, you can go to the left of the Pokemon League entrance to obtain the Mewtwonite Y.
Houndour can be obtained by trading from Pokemon X or Y. It cannot be caught in the wild in Pokemon Omega Ruby and Alpha Sapphire.
On field, it'll attract Pokemon to you. In Pokemon X/Y/Omega Ruby/Alpha Sapphire, you can now attract hordes of Pokemon. In battle, it decreases your opponent's evasiveness.
Sandslash learns Dig at level 30 in Pokemon X and Y. In Pokemon Omega Ruby and Alpha Sapphire, it can learn Dig at level 33.
Trapinch can learn Dig by itself at level 29 in Pokemon X and Y. In Pokemon Omega Ruby and Alpha Sapphire, it can learn Dig at level 19.
Ursaring learns Hammer Arm at level 67 in Pokemon X, Y, Omega Ruby, and Alpha Sapphire.
Sandshrew learns Dig at level 30 in Pokemon X, Y, Omega Ruby, and Alpha Sapphire. It can be taught faster if you used the TM28.
There are currently no known upcoming events for Pokemon involving Arceus. It is possible there could be an event for Pokemon X and Y or Omega Ruby and Alpha Sapphire but there seems to be no plans as of yet.