One of two scenarios:
1) You're using full height studs because there's no floor diaphragm there to brace them, so your shear wall is two stories high.
2) You design a wind girt to support the wall at what would otherwise be a hinge.
In both cases, you need to get load out of the second floor diaphragm and into your walls. This will happen with a collector. It's typically the the rim board or the top plate of the lower wall. So the diaphragm transfer in that area to the upper right has to be sufficient to dump the load into that collector, and then the collector has to deliver it to that first floor shear wall. Presumably the roof diaphragm load is going straight through the stacked walls.
Then, if you want to really design it properly, you need to consider sub/transfer diaphragms to get the load from the the main diaphragm out past the re-entrant corner formed by the stair.