[Android] Can I use Muserk music to remove the watermark?

No, on KineMaster v4.13 or higher, it's not allowed to use Muserk music to remove the watermark.

If you have some Muserk music already downloaded and stored in your device, you can use it just like ordinary audio, but you can't use it to remove the watermark from the video to be uploaded to YouTube.

Besides, no matter if you're a subscriber or a free user, the video including Muserk music can't be free from copyright claims. You're recommended to use KineMaster music which you can download from KineMaster Asset Store without concern about copyright issues.