There was a suggestion of how to fool a PPC Mac into running flash content with a patched version that made the system 'think' it has a later one. In some cases this works.
"...version 10.1.102.64 is the last version available to PPC Mac users**. The latest version,10.3.183.23 or later, is for Intel Macs only running Tiger or Leopard, as Adobe no longer support the PPC..."
** https://discussions.apple.com/thread/5215021?answerId=22647728022#22647728022
see link below* for flash 11.5 later patch than one in this ASC page
To see what your computer is running and for links to 'standard Adobe flash player' versions:
•Flash Player Help - Adobe Flash Player:
http://helpx.adobe.com/flash-player.html
•Unofficial - *Adobe Flash 11.5 for PowerPC:
http://scriptogr.am/nordkril/post/adobe-flash-11.5-for-powerpc
The rules for uninstalling the older or former player are not the same,
note there are methods inside the unofficial update to follow. And as
things change over time, Flash player is a moving target that not all
systems or patches could hope to keep up with. You update only part
of the Flash player, I'd save the older part in a separate folder, just in
case the patch doesnt help all that much. It works in my PPC 10.5.8.
Good luck & happy computing! 🙂