You absolutely aren't copying the work, recompilation projects are intensive work and a re-imagining of what the source code could look like. Compilation is still a one way process.
And then for the legal part, that's why it's called an exception.
There is little to no creative work whatsoever if you end up with exactly the same game; and often they end up with exactly the same binary as well. Source translations are derivative works almost by definition. It doesn't matter what magic you use to generate it.
And again, where is the interoperability here? Interoperability exception would apply if there was whitebox cryptography, Nintendo logo-style things or anything else where the only method for the work to run would be to violate copyright of _exactly that_. Under no circumstances you can simply copy & distribute the entire work (or derivates) while claiming "interoperability exception!". It makes utterly no sense.
There is little to no creative work whatsoever if you end up with exactly the same game; and often they end up with exactly the same binary as well. Source translations are derivative works almost by definition. It doesn't matter what magic you use to generate it.
And again, where is the interoperability here? Interoperability exception would apply if there was whitebox cryptography, Nintendo logo-style things or anything else where the only method for the work to run would be to violate copyright of _exactly that_. Under no circumstances you can simply copy & distribute the entire work (or derivates) while claiming "interoperability exception!". It makes utterly no sense.