In general zoysia is not shade tolerant; however, there are some varieties which are very shade tolerant. One, which is no longer available, was called Shadow Turf. If you find references to that on the Interwebs, it is no longer available. It was a hybrid of the Manila type of zoysia (not the japonica varieties). The grower was an agricultural hybridizer for crop production. Their venture into turf apparently did pan out. I kinda miss them, because they had a really good buffalo grass and the shade tolerant zoysia. You might contact these guys at
Ivey Gardens Greenhouses, as they discovered the grass which became Shadow Turf.
Here's more on zoysia from Wikipedia
Zoysia matrella (Manila type of zoysia)
It forms extensive, velvety, green mats, spreading vigorously by stolons, or occasionally by rhizomes, once established. Z. matrella grows in low elevation preferring sandy soils where other grasses establish poorly. The stems are slender and prostrate, ranging from 5–25 cm in length. The leaves are alternate, produced at 1.5–3 cm intervals along the stem; they are slender, 2–10 cm long and 1–3 mm broad. The flowers are greenish, produced on erect racemes 6–35 mm long with a single 2-3.5 mm flower in each spikelet.
zoysia japonica
Parade Magazine grass
coarse bladed, can be seeded, needs humidity to survive
Varieties include
El Toro
Belair
Meyer
Midwest
Palisades
JaMur
Empire
Zenith
Compadre
Emerald Zoysia
Fine bladed hybrid of z. japonica and z. matrella
Should be mowed with a reel type mower
Slow growing and spreading as compared with other slow growing zoysias
Can be sensitive to excess fertilizer and die out