I’ve collected polls of France’s Emmanuel Macron (but this site shows less improvement for him); Italy’s Giuseppe Conte; New York’s Andrew Cuomo; Poland’s Andrzej Duda; and the UK’s Boris Johnson (the Tories now have their best support in the history of British polling). For Australia, Brazil, Canada, Germany, and Mexico, I am using Morning Consult polls from here. I take Trump’s approval rating from FiveThirtyEight. Countries with strong parliaments and weak executive branch leaders typically do not poll their national leaders often.
The graph below shows how various national populations rate their own leaders’ handling of the pandemic. (It is from the Canadian Broadcasting Corporation, hence the three Canadian leaders.) Note that Macron is rated worse than Trump on handling the virus but still gets a bigger bounce in approval polls.