RAW no, because twinned spell only works on a spell that can only target 1 creature and Aganazzar's scorcher targets a line of creatures 30' long and 5' wide.
The rule for twinned spell is basically "if there is a situation where the spell's effect (at current spell level) could affect more than one creature, that spell can't be twinned even if that situation is not present."
In this case, Aganazzar's scorcher could effect multiple creatures in a line, so it cant be twinned even if creatures are not lined up in range.
Does twinned spell work on Aganazzar’s scorcher?
RAW no, because twinned spell only works on a spell that can only target 1 creature and Aganazzar's scorcher targets a line of creatures 30' long and 5' wide.
The rule for twinned spell is basically "if there is a situation where the spell's effect (at current spell level) could affect more than one creature, that spell can't be twinned even if that situation is not present."
In this case, Aganazzar's scorcher could effect multiple creatures in a line, so it cant be twinned even if creatures are not lined up in range.
The only argument I have is potentially the difference between “targeting” vs “affecting”.
the spell is “targeting” self, but “affecting” more