If you provide more context or details about Eagler 1.9, I'd be happy to try and assist you further!
This is the most common concern. Eagler 1.9 is not supported or endorsed by Mojang or Microsoft. It is a reverse-engineered project created by independent developers for educational and archival purposes. eagler 1.9
This represents a more advanced rendering approach, featuring "a deferred physically-based renderer modeled after the GTA V rendering engine with many new improvements and a novel raytracing technique for fast realistic reflections". While impressive, this represents a different technical direction from simply porting newer Minecraft versions. If you provide more context or details about Eagler 1