You are trying to load a save from a version of Eastern Sun that doesn't match your current install.
Instead of hunting online, you can create your own repository of Eastern Sun character saves.
Do not hoard thousands of high-attribute items on a single character or shared stash page. Keep your stash organized and delete junk items periodically. Mod Version Discrepancies Diablo 2 Eastern Sun Character Saves
If stuck:
Eastern Sun has gone through many iterations. Ensure the saved character version matches the mod version you are running. You are trying to load a save from
Paste these files into a separate backup folder on your desktop or an external drive. For maximum security, compress them into a .zip or .rar archive labeled with the date and your character's current level. Troubleshooting Common Save File Issues Error: "Bad Inventory Data" or "Bad Character Version"
[Diablo II Install Folder]\save\ES\
The Eastern Sun mod typically installs as a subfolder within your main Diablo II directory. Because this mod uses a modified engine to allow for more stash space and new skill tabs, the save path is specific. Check Diablo II/Eastern Sun/save .
When using PlugY, your shared stash is saved in a file called _SharedStashSave.sss or _SharedStashSave.d2x inside your save folder. Keep your stash organized and delete junk items periodically
If a restored character does not appear: