Yeah I found it funny how similar yet very different our games seem to be. My buddy programmed everything in Unreal Engine 4 (since UE5 can't do browser games).
The graphics for the game were largely made in Blender, but rendered out as 2D sprites using fresnel and emission shading. I used a seamless voronoi texture loop (same as you did, I think) for the watery animation, made that partially transparent, and then made giant blurry cells which my buddy programmed to float around randomly underneath the transparent voronoi animation. He also coded the color to shift with each wave by color-tinting a desaturated background image.
Thanks for the kind words!