Is Undertale Sans from Deltarune's World?

Is Sans from Undertale the same Sans as in Deltarune? This Deltarune theory has been floating around since 2018, and today I discuss its evidence, its holes

Hmm, could that other world be the Deltarune universe? : r/Undertale

Undertale and deltarune are connected

Deltarune Explained - What's the Connection to Undertale? - GameRevolution

sans undertale meets sans deltarune : r/Deltarune

How Sans' Appearance in Deltarune Opens Connections to Undertale

Deltarune Explained - What's the Connection to Undertale? - GameRevolution

Ways Deltarune Connects To Undertale

Stream DELTARUNE - REVOLVANIA (THE WORLD REVOLVING x Megalovania Remix) by RetroSpecter

Deltarune Explained - What's the Connection to Undertale? - GameRevolution