Forex is a completely different market from stocks and ETFs. It doesn't trade the same, and it's affected by somewhat different forces.
For example, USD-NOK is heavily affected by oil prices. High oil prices means demand for Norwegian oil assets, which drives up the value of the currency. Low oil prices drops the value of the NOK.
Japanese yen value seems to be mostly steered by the low interest rates in Japan and the resulting carry trade. People borrow enormous amounts of JPY and then have to sell it to buy dollars, pushing down the value of the JPY compared to the USD. This is probably the easiest pair to trade right now if you follow Japanese interest rates and carry trade cycles.