How do you actually test UGC variants when your messaging needs to hit two different cultural angles?

Testing UGC has become way more complex for me since we started running cross-market campaigns. In a single market, A/B testing is straightforward—you change one variable, measure the lift, move forward. But when you’re testing across two markets with different cultural contexts, the whole methodology gets fuzzy.

Here’s the challenge I’m wrestling with: let’s say we have a core UGC message about sustainability. In the US, that message might emphasize individual environmental responsibility and personal impact. In Russia, the same message might resonate better if it’s framed around family heritage and passing values to the next generation.

So are we testing the same content in two markets, or are we testing two different creative directions that both align with the core brand promise? Because those are fundamentally different experiments. And the statistical rigor gets messy when you’re not comparing apples to apples.

What’s your actual process? Do you run separate testing tracks for each market and accept that you won’t get clean statistical comparison? Or are you doing something smarter that I’m missing? How do you balance rigorous measurement with the reality that authentic cross-market content requires different cultural angles?