The best way to make this 'work' is improvements to interlanguage links to make them clean metadata; then we can easily pull the same links from the subject page and show them on the talk page (actually, we could probably do that already -- pulling the recorded langlinks from the subject page). Though adjusting automatically to the matching talk page might take more workish.
They should, however, always be a matched pair, not separately added.
T102888: [Bug] Recent changes pages doesn't have anymore the interlingual wikilinks on the sidebar on some projects
T123063: Special pages should link to all languages in a project.