They already have GraalJS which is afaik up-to-date with the EcmaScript spec and has insane throughput (on long-running tasks it has comparable speed to V8, with a much much smaller team behind it) - it can AOT compile said code as well, but I’m not sure about the performance characteristics of that.
Java is static-typed already and only has a low degree of dynamism, so the importance of doing so is much less (only to reduce the initialization time I believe).
There's a lot of interfaces and virtual calls in Java. Not sure if you're considering that dynamic or not, but I would would. Graal does some pretty intense whole-universe points-to analysis which enables monomorphisation, devirtualisation, scalar replacement, etc.
Java is yes, but the JVM runs other things and things like JRuby use the JVM bytecode for invoke_dynamic. There were a few things rewritten to use that bytecode from what I remember but it's been a while since I've worked in that area.