Would blindsight allow a blinded caster to cast spells that specify the target as a creature "that you can see"?
Would blindsight be able to substitute for the requirement of having to see a creature to target it (assuming the target was within the range of the caster's blindsight and spell)?
Let's assuming I'm playing a character who is blind, but also has "blindsight" out to 10'ft. Blindsight would let me know where a creature is near me, and even make melee attacks without disadvantage. Would it let me target a spell at that same creature?
Alternately, if an old blind dragon with blindsight wanted to use an ability or power that requires them to be able to see a target, could they still use it?