I am pretty sure that the only elven blades that glowed in the presence of orcs were those made in Gondolin. I think this was said in The Hobbit and not mentioned at all in either Lord of the Rings or the Silmarillion. I think that JRRT came up with the idea for the Hobbit and had to continue with it for LOTR despite not using at any other time in his legendarium.
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His sword was long his lance was keen
His shining helm afar was seen
The countless stars of heavens field
Were mirrored in his silver shield
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