I know this is very very old topic but found more information regarding the Dark, Light, and Annihilator Bomb
Dark Bomb (power bomb upgrade)
“The Dark Bomb combines the power of the Dark Beam with that of the Power Bomb.
When in Morph Ball mode, press [C-Right] to select the Dark Beam, then press [Y] to drop a Dark Bomb.
Dark Bombs release a field of dark matter tendrils when they detonate. These tendrils can entangle and hinder enemies.
Dark Bombs are not effective against Denzium.”
Light Bomb(power bomb upgrade)
The Light Bomb combines the power of the Light Beam with that of the Power Bomb.
When in Morph Ball mode, press [C-Down] to select the Light Beam, then press [Y] to drop a Light Bomb.
Light Bombs do not detonate on release. They explode when an enemy enters their detection radius, or when another Light Bomb goes off.
Light Bomb explosions are white-hot, and can set enemies on fire.
The brilliance of Light Bomb explosions can blind and stun dark creatures.
The Light Bomb is not effective against Denzium.
Annihilator Bomb(power bomb upgrade)
The Annihilator Bomb is a potent explosive, combining the Power Bomb with the energies of the Light and Dark Beams.
When in Morph Ball mode, press [C-Left] to select the Annihilator Beam, then press [Y] to drop an Annihilator Bomb.
When an Annihilator Bomb detonates, it emits a cloud of Light and Dark energy particles. These deadly particles will seek all enemies within a radius.
The Annihilator Bomb is not effective against Denzium.
These kinda remind me of Super Metroid power bomb beam combos, would have been cool if they made it into the finale game and gave more boss fight in Metroid Prime 2; here’s a video link of them
Ingame beta of the bombs
Makes me wish they make the Ultimate Metroid Prime Triliogy for the Switch with 1080p and program these bombs into the game.