You are a bit late to the party. Many Russian assets have already been seized, among them the Gazprom subsidiary in Germany.

We are in a weird spot where Russia is very much interested in economic relationships continuing more or less as is (exemplified by the conciliatory rhetoric from the Russian government, essentially they are saying "no hard feelings, return any time" to the departing companies) so will mostly respect property rights. OTOH the West sees financial and economic relationships as their main weapon in this war so most funky moves related to property rights will be initiated by the Western governments (e.g. many "sanctions" essentially are extrajudiciary property seizures).