The Mamiya 645 210 f/4 is my favourite in 6x4.5. It doesn't crop particularly tightly (about 1/10 life-size or 406 mm by 547 mm), but the working distance is really comfortable.

Alternately, the Mamiya 645 110mm f/2.8 allows a slightly tighter crop and a shorter working distance.

The closest, non-macro Mamiya 645 short telephoto? - The relatively rare Soft Focus 145mm f/4 - 1/13 life-size and 326 mm by 440 mm.

On the 6 x7 side, I like my RB67 140mm macro, but it might be too sharp for some portraits.