The best candidate to finding a lot of minimal pairs is using a frequency list for any given language.
grzegorz already provides functionality for getting one, through the
wordlist command. You tell it what language you want your wordlist in and the
number of words it should keep in it.
If you want to know what languages you can do that for, use the list-languages
function. You may use the language code or the language name itself.
Let's suppose you wanted to save the most common 20000 Polish words to a file
called polish-wordlist.txt. In your terminal, you would run:
grzegorz wordlist polish 20000 polish-wordlist.txt
Alternatively, using the language code:
grzegorz wordlist pl 20000 polish-wordlist.txt
You may also specify a lower and an upper bound instead of the absolute upper
bound, such as 25000:50000, which takes only the words from index 25000 in the
word list up until index 50000. Here's an example of what that would look like:
grzegorz wordlist romanian 25000:50000 romanian-wordlilst.txt
But a wordlist on its own is rather underwhelming. There's one more step before finding minimal pairs, and that is fetching word IPAs