Is the 10 year yield a leading indicator for usd/jpy or vice versa? Does anyone pairs trade using these 2 instruments? I have heard fund managers mentioned that these are the 2 more stable instruments to get consistent results but what is the strategy? Mean reversion or something else?
You can try to regress returns of US10Y to JPY returns with a lag to test that hypothesis. Visual overlaps gives you just an idea that connection between two variables exists but I don't recommend to use to accept it without proof.