Text from the now defunct section of Transformers.com with Energon character bios, as seen on Wikipedia.

Primitive in thought and simple in speech, what Grimlock and Swoop lack in intelligence they make up for in strength. They have given the Autobots the tactical upper-hand in battle time and again sending Decepticon legions retreating in fear. Swoop will often use his impressive aerial maneuvers to confuse and distract an enemy while Grimlock sneaks from behind and stomps that enemy before they even know what hit them. They then use their combined strength to ensure that there is little left of their unfortunate prey. Although they are armed to the nines with powerful weaponry, Grimlock and Swoop prefer to take down their enemies with razor sharp teeth and talons.

Little is known about the intended personas of Energon Grimlock and Swoop.  Whether you see them as related to the G1 versions or those of any other Transformers generation, likely depends upon whether you see the Unicron Trilogy Series (Energon) as connected with any other Transformers continuity.

Other appearances: Below is a complete list appearances throughout the Transformers mythology: 

* 1985 was the first Original Grimlock and Swoop
* 1989 released as Classic Pretender
* 1990 in Action Master form
* 1993 the G1 toy was recolored in gray, blue and turquoise for G2.  Swoop was not.
* 1997 in Beast Wars Grimlock
* 2001 in TF: RID sorry, no character page yet...
* 2003 Dinobots Grimlock and "Swoop" was actually named Terranotron.
* 2004 an Energon Combiner
* 2007 a Classics Minicon Swoop, Classics Grimlock and 3" Titanium Grimlock
* 2008 Animated deluxe Swoop and Grimlock,  Titanium War Within Grimlock and Activator Grimlock.
* 2009 25th Anniversary Masterpiece Grimlock is coming.

Bibliography of significant appearances: None in this form. 

Shown below, and in other angles in the photo gallery above, see how Grimlock and Swoop unite to form, "Mega Dinobot!"  Click each picture to see in higher resolution.