I'm experiencing this for a long time and I am unable to solve this problem,
I save lyrics using stellio pro for offline use & it's works like charm but Poweramp can't show them properly for some reason (few songs show messed up lyrics unable to read) other players (Rocket, black player etc) & many other premium players show them properly but I can't upload screenshots I uninstalled all of them because of their terrible sound quality
Here's some screenshot of Poweramp and Stelio itself (please note that the lyrics stored in tags)