I’m going to say the cow with the weird face could have been painted at any time:
This rings true to me. My guess is it was painted by some relatively new (or indifferent) worker at the factory when they were making tons of those tiles. Which also matches what the seller told the OP.
Later in the 19th century, designers like William Morris (1834 – 96) and William De Morgan (1839 – 1917) revitalised interest in Dutch tiles. Morris used blue and white Dutch tiles to decorate areas in his home, Red House, in Bexleyheath. Morris and De Morgan also invested commercially in the Dutch tile market by buying in glazed and fired blank tiles from the Netherlands on which to produce their own designs.
Please do note, though, that I have conceded argument on the point about the cow-faced tiles upthread being later than the Japanese Kudan.
I’m very familiar with the Arts&Crafts majolica revival, but it tends to be polychrome repeat patterns, not the blue-on-white singular figurative stuff we’re discussing here.
I don’t think the blue on white ever really went away - here’s an example of tiles from the early 20th century, for example; Here’s a collection spanning 18th and early 19th; here’s one from later in the 19th.
At some point in the 19th century, printed transferware overtook hand painting and iron (brown and red) underglazes competed with tin (blue). Certainly the popularity was not constantly high, but I don’t think it ever went away. You can still buy new delft tiles today.
I didn’t say it did - but it wasn’t William Morris and William De Morgan doing it.
I already mentioned the 20th C revival myself, and you get how a “collection covering the 18th and 19th C” includes the OP’s date, right?
If the seller claimed it was from the 18th century
And there were scads of them manufactured in the 18th century, and lots of those are still around and are easy to buy, why would you assume it was produced at any other time?