We have a nice short opportunity in these charts.
It's more evident in the case of USDJPY which offers a clear target and invalidation level.
In the case of the Nikkei, it's at the level of a long term resistance, and showing a painful advance, not something I'd consider bullish in my view, and to make things worse, the highest low has been taken out by a down bar.
We can enter short positions with confidence, keeping a reasonable stop, based on 3 ATR(11) in the case of the Nikkei, and slightly above my purple invalidation level in the case of USDJPY.
Target would be the horizontal line below initially, where I'd suggest covering half of the position and moving the stop loss to break even in case it continues to fall.