Asian Brown Flycatcher is Kansai's only widespread breeding muscicapa and it's quite common in broadleaf forests. I see many in the Ashyu area for example. They are quite common in and around Kyoto city during spring and autumn passage and will turn up in any area with trees, from those lining riversides to city parks and the surrounding hills. Similarly Grey-streaked, which doesn't breed in Japan, is common on migration in the same places and at the same time, the early September to mid-October period is best.
Though Dark-sided Flycatcher breeds in Hokkaido and upland areas including the Kii Peninsular it is surprisingly uncommon, rare even, in the Kyoto area as a migrant and definitely can't be expected when visiting Kansai.
Ferruginous Flycatcher is the only other muscicapa occurring in Japan but it's a major rarity.
They can be very common in riverside parks, along with Asian Brown, this one on the Katsura River (Kyoto city) 7 October 2010.
This Dark-sided almost slipped by unnoticed, front-on it could easily pass for a messy Grey-streaked. The poorly marked lores, dusky lower belly and streaked undertail coverts confirm the identity. Katura River 3 October 2010.
The bird below is a weird looking Asian Brown Flycatcher on Hegurajima. On a beautiful calm sunny day following a couple of dreadful days all the muscicapa flycatchers were perching on the tree tops while this thing was flitting through the lower skirts of a plantation, frequently dropping to the ground. I fully expected it to be ficedula however its appearance didn't match anything I've seen. Ferruginous was no more likely despite the warm underparts and partial grey upperparts being superficially suggestive. The aberrant colouration aside, the markings fit Asian Brown which is what it must be.
The upperparts were a warm, light brown, unlike the normal colder greyish-brown, but most surprising it had broad, grey lateral crown stripes, nape and mantle. The underparts were a pale golden colour which only shows slightly in the final shot. Apart from the aberrant colouration (and atypical behaviour compared to others on the day) the markings fit Asian Brown.