proot works by hijacking and altering syscalls. So maybe you could emulate the symlink yourself, by altering the file paths at ptrace level? Thinking more, may

proot works by hijacking and altering syscalls. So maybe you could emulate the symlink yourself, by altering the file paths at ptrace level? Thinking more, maybe it works out of the box? Just mount the overlays (there's a cli flag IIRC) and proot takes care of syscalls by definition.