taking away access to (non-public/SNS) intermediary services (like the ICC prosecutor's email account) seems like the same sort of issue, with speech/association-related impacts. Domain name seizures (and similar seizures of property) may also have similar takedown-like effects. But that's probably
beyond the scope of what you're asking. As a bonus, and while on the topic of sanctions, one might wonder how interoperability would work with a sanctioned foreign SNS. Meta's Article 7 DMA reference offer rules out interop sanctioned entities... Doubt that's permissible under the DMA though.
Oooh, that one sounds like a potential hard conflict. If EU law requires interoperating with someone/an entity on the export controls list? I think that's a big deal, like a countries-need-to-sort-that-out level deal. Or if we had all sane countries that would be how this should work.