This bird is certainly not Swinhoe's. The bird is too large, and the proportions do not really fit - especially the bill which is fairly long in Swinhoe's. Swinhoe's is a small egret, and the confusion would be with Little Egret. Non-breeding Swinhoe's has a dark bill and is very difficult to separate from Little - you need to check bill shape (thicker and blunter-tipped, not tapering to a point as in Little, but still relatively long), leg length, leg/foot colour, etc
Intermediate is actually much more likely to be confused with Eastern Cattle Egret than Swinhoe's.
I'm actually with Ho fai on this bird, in that I think it's difficult on this photo to rule out Great Egret. Some Greats are not as obvious as you might think - looking smaller with shorter, thicker necks and shorter bills - and therefore more like Intermediate. For me, the bird in your photos does not look as short-billed and round-headed as I expect for Intermediate. But I'm not really sure about the ID of this individual from this one photo.
