https://covariants.org/per-country
Here is some data showing variant percentages in some countries. Many of the countries where Delta has become dominant are seeing increases in cases. e.g. UK, Portugal, Russia, Indonesia, even though it is summer in the NH. Latter two countries on this list (Russia, Indonesia) are seeing notable increase in deaths, and are also lagging in vaccinations.
Finland and Canada however are still seeing declining cases so far.