The reason for this request is that, frankly, scythes are an incredibly dumb weapon. They are a farming implement that is incredibly unwieldy to use in combat. But there is a type of scythe that is a viable combat weapon: the war scythe. The war scythe is essentially the blade part of the scythe turned so that it faces vertically instead of horizontally.
Adding the glaive appearance options to scythes would allow scythe-users to replicate war scythes.
There is also the fauchard, which is an evolution of the war scythe with an even closer resemblance to glaives.
Glaive appearances that should be added as an option for scythes:
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