Maybe ReShade doesn't like the engine. If you think it's a compatibility issue with jME, you can go to
their troubleshooting forum, where the ReShade community may be able to help assess the issue. From what I can tell, jME is off the radar of ReShade's community, so you'd be helping out lots of others in your situation by inquiring
Best of luck!
I can't tell if it's a compatibility issue, because I can't even hook into the executable and produce a log from ReShade telling me about any issues.
I don't know anything about reshade... but note: Mythruna does not include its own Java. It uses the Java on your system.
Hrmmm, that's odd. I have ReShade installed to all Java directories but it just doesn't work. And maybe I'm paranoid but I read something about jME with it in a client.log... I'm sure I'm wrong now though xD.
Is Mythruna 64bit or 32bit? (asking now because I don't have access to a computer and I've never actually checked, but I guess 32bit. Or, rather, does that depend if your Java version is 64/32?)
I'll go into to more testing and delve deeper into my amateur knowledge to figure out how to work this. :p.