Exactly what I was thinking as well but it's slightly more detailed and 'finer'.
Either way. Always awesome to see artists finding interpretations so fast!
For sure on all points. To defend Oda, he is pressed for time so he cannot add this level of detail in the manga. I assume Oda could do it, but it wouldn't be his specialty.
That's some crazy level of skill though. This was a week ago and they followed the same 3-steps of how Oda draws for color spreads (a rough sketch, the finalized drawing, and then touch ups for shading/detail). THIS person needs to be hired as one of Oda's assistants...they can obviously mimic the style of work both accurately and quickly.