Can a sor-lock be able to use twinned spell and quicken meta magics to triple the eldritch blast?

PHB has it under Meta Magic as

You can use only one Metamagic option on a spell when you cast it, unless otherwise noted.

In theory this means

action = Twinned eldritch blast

bonus action = Quickened eldritch blast

The spells would be considered different spell castings correct?

You can only twin Eldritch Blast between level 1 and 4. Once you hit level 5 it shoots 2 beams and can target more than 1 enemy making it an invalid option for Twinning.

But yes - at 4 or below you can do that.

And at that level it would be impossible to have agonizing blast (level 3 sorc for metamagic, level 2 lock for agonizing blast).

As far as I'm aware, the only way to cast EB three times in a turn is to Quicken one, cast the next one as your action, and then Action Surge. So.. ideally 2 levels in warlock (for Agonizing Blast, though 1 level or the Spell Sniper feat would work), 3 levels in sorcerer, 2 levels in fighter.

Might as well use the meta magic to optimize damage rolls. Forget what it was, empowered spell maybe.

If you were a wild magic sorcerer and only went the 2 levels in warlock, could get mileage with the eldritch blast spam and spell bombardment. Most people don't play level 20 campaigns though.