IMPORTANT: 

If you want to do the voice modulation yourself, that's fine. But for audition sake, I need an audio with and without modulation. 

Voice description*: Compared to OG sans, ERROR is a helluva lot more sadistic and self centered. Voice wise, he's probably the most similar to a normal sans voice, his voice "quirk" (for lack of a better word) is the modulation that is usually put on his voice, making it sound unstable and glitchy. 

For reference, Audiospawn's ERROR!!!sans, though it doesn't really need to be so deep.

*Note: Like all voiceless characters, this is up to interpretation. If you have your own interpretation of this character's voice, by all means try it!

Personality and Bio from UT OC Wiki

Personality:

He has a selfish and playful personality and thinks he's helping out the multiverse. He steals things, raids and destroys AUs to name a few things he does. He loves to play jokes, and make snarky teases at his enemies. Canonically, he doesn't get mad until things don't go his way, how he expected it to happen, or when others trigger one of his fears. And although he has a lot of hatred toward non-canon materials regarding Undertale, the ones that slightly deviate from the original annoys him the most.This makes him, as the creator best put it, a literal man baby.

Bio:

Error is a version of Aftertale Sans (Geno) that messes around with dangerous determination magic, even with warnings from Sans. He eventually accidentally sends himself to the anti-void. To which, in his final moments of sanity, he's furious that even though he got his happy ending, this had to happen. Geno lost his sanity to hating everyone and anyone except for himself, which is why Error is so hateful and calls everyone 'glitches' or 'abominations'.