Technically, no effect since Force isn't an energy type. It is a descriptor and some Force effects call themselves out as being of the force damage type (others are just untyped, so it's inconsistent), but it's still not an energy type so energy resistance doesn't apply.
I'd recommend splitting the energy type listing in the ideals into two. One for the damage type (as used by Blade and Breath and probably other idealist features going forwards), and one for resistances and the like (as used by Scales).
For example...
Black Dragon
Damage: Acid damage
Resistance: Acid resistance
Amethyst Dragon
Damage: Untyped (treat as resulting from a Force effect)
Resistance: Reduces damage taken from Force effects
Crystal
Damage: Untyped (treat as resulting from a Light effect). Damage is reduced by 1 die size, but deals double damage to creatures particularly vulnerable to light.
Resistance: Untyped bonus on saves against dazzling, blindness, and Light effects.
Speaking of which, Crystal Dragon's blindness on the breath weapon should be one of the ideal powers, not baked into the breath itself. Untyped damage is strong enough as-is.
Force Dragon I is missing the closing parenthesis.
Force Scales can easily be a penalty, since it means you can't benefit from deflection bonuses.
Fang Dragon's bite attack needs an actual damage value for characters who aren't Wyrm Warriors.
Fang Dragon's dispelling should be Greater Dispel Magic.
Also, web dragons for your list.
Steel Dragon (weren't they reprinted in one of the Faerun books?)
Mist DragonMercury DragonTemporal Drake (not a true dragon, but very neat)