The correlation between currencies are way too complicated. Instead, we can only confirm the strength of that currency vs USD.
For example, when trading NZDxxx pairs, we only trade BUYS when NZD>USD.
I had claude make me such an indicator. Maybe it can be used as confirmation, feel free to propose for improvement or debunk me

EDİT: With composite-timeframe set at 14, it gives almost EXACTLY same results with the 3x XUMA, idk this was a good idea or not