Here are a few options for a formal equivalent, depending on your preferred level of nuance:
Option 1 (Most direct and formal):
“Coordinated Hybrid Disinformation Campaign Targets Baltic States”
Option 2 (Emphasizing the strategic nature):
“The Baltic States Confront a Systematic Hybrid Disinformation Campaign”
Option 3 (Academic/Policy tone):
“Strategic Disinformation Operations Directed Against the Baltic States”
Recommendation: If this is for a formal report or a professional article, Option 1 is the most standard and effective choice.