Some are doable, I think, but not all.
With some different POD's, Spain's minority languages can become more prevalent. Honestly all it would take is a 1970's cultural revival in Galicia, Vasco, and Catalonia (even though that kind of already happened in Catalonia).
For the UK, perhaps if the 1960's go a little differently and the imperial guilt angle is played up, then the government could invest in programs that promote the Welsh and Scots languages.
Similarly the Netherlands could become interested in West Frisian and all the tiny populations speaking unintelligible languages for whatever reason, especially if there is international pressure to promote minority languages (perhaps coming from Spain and the UK themselves), but I think this is less likely.
Belgium, Canada, and Switzerland are OTL, of course, but I suppose if the eastern Canada economic depression starts earlier, Quebecois "cultural imperialism" (for lack of a more sensitive word) could make bigger inroads into New Brunswick and maybe even Ontario surrounding Ottawa.
So far we haven't even really changed history that much.
But there are some western nations where I think this multilingual situation CANNOT happen: Portugal, France, Germany, Italy
Portugal simply didn't really have any languages besides Portuguese, that was kind of the point. They're innocently monolingual, in the same way that Finland is innocently racially pure.
In France, Germany, and Italy, I think nationalism is way too powerful of a force to let minority languages survive. Speaking the national language was an integral part of their country's unification process (or in France's case, holding the country together over the centuries).
The US could theoretically end up multilingual, especially with German as a regional language and Spanish as a regional language. But to get a US in which people on the Plains preferentially speak German and in which white people learn Spanish as well as use it with each other require some history-changing POD's.
Also like people said, if somehow Austria-Hungary reforms, that obviously adds to the list.