Apart from the Battle Frontier, no.
No. You can migrate Kanto Pokemon to your Platinum or catch some in the wild, but you cannot access one region from a game set in another region.
No.
You can't, the only region you can go to in Pearl, Diamond and Platinum is Sinnoh.
In Pokemon Platinum you can't go to any other (that includes Kanto) region. I know it's upsetting, but you can still have fun by catching uncommon Pokemon!
You never will go to a different region.
No. You stay in the Sinnoh Region the whole time.
NO
once you have seen all the Pokemon in the Sinnoh region go to Professor Rowan and he will give it to you
Surf west of Jubilife City
U CAN NOT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
there is no platinum for gameboy. theres no zheri region. wake up, dude! if ur talking about DS , go to great mrash.
There is no temple of the sea in Pokemon Platinum. In order to get Manaphy in Pokemon Platinum you need to go to Manaphy's special event at any Gamestop (special events are very rare). The temple of the sea isn't in the Sinnoh region.