What is the algorithm of the service similar to rifmus.net/tech?

Question

Algorithms

Good afternoon!
I’m interested in what algorithms such a service works on rifmus.net/tech I’m
especially interested in the moment of accentuation I
already looked for information about different algorithms like Soundex, Daitch-Mokotoff Soundex, NYSIIS, Metaphone, Double Metaphone, Russian Metaphone, Caverphone
But I’m interested in which algorithm and how it works with accents