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

Regarding Sans and the Timeline : r/Deltarune

More evidence that sans is from the world of Deltarune! : r/Undertale

Deltarune Sans Winks Sticker - Sticker Mania

Deltarune memes and pixel art, explained - Polygon

Kris dark world deltarune

Dark World Muffet/Sans by killb94 on DeviantArt

Deltarune dev announces major release date change for upcoming chapters - Dexerto

Post-Ch2 Deltarune Theories / GioCities

What do you feel is the most interesting character in Undertale that's not a major character (The Dreemurr family, Undyne and Alphys, the Skeleton Bros., etc.)? - Quora

Sans CONNECTS Deltarune to Undertale! (Deltarune Theories)

Undertale's Toby Fox gives a tantalizing Deltarune update

Deltarune Chapter 2: A Cyber's World / Funny - TV Tropes