Better pattern: maybe it’s : each key pressed one key to the left on QWERTY.
But possible if it’s or a code where each ciphertext word is a common word with vowels replaced: a→a, e→y, i→y sometimes? Actually in media → mydya : m m, e→y, d d, i→y, a a. So ciphertext y = either e or i in plaintext. That’s possible if the cipher just replaces vowels with y randomly or by position. thmyl lbt jyms bwnd llandrwyd mn mydya fayr
But apply ROT13 to all:
Shift of -5: