I see literally no connections other than the pixel style and the black and white color scheme.
And those are hardly Undertale staples.
What exactly are the similarities you see?
some examples that I see similar to undertale from the description
Traverse through a nightmare like realm similar to undertale
You play as a silent effeminate Protagonist, seemingly dropped into this world, now you must survive and find a path out similar to undertale
one primary weapon similar to undertal