Film
In 2015, Velberg made his film debut in the Ronet Tänav-directed Baltic Film, Media, Arts and Communication School of Tallinn University comedy short film Kivamees, opposite Estonian Academy of Music and Theatre classmate Pääru Oja and Doris Tislar. The same year, he was cast in a starring role of Karl Tammik in the feature-length war drama 1944, directed by former Estonian Academy of Music and Theatre course supervisor Elmo Nüganen. The film premiered in February 2015 in Berlin, Germany, before its release in Estonia. It was selected as the Estonian entry for the Best Foreign Language Film at the 88th Academy Awards, but it was not nominated.
The following year, he appeared as Ralf in the Anu Aun directed Luxfilm youth drama Polaarpoiss. In 2018, he was cast in a starring role as Igor in the Ari Alexander Ergis Magnússon directed Icelandic-Estonian coproduction drama film Mihkel, opposite actors Tómas Lemarquis, Pääru Oja, and Atli Rafn Sigurðsson.
Velberg has also appeared in several foreign-language films. In 2020, he appeared in a small role as a police operator in the Christopher Nolan directed Warner Bros. Pictures English-language science fiction action thriller Tenet, which was filmed, in part, in Estonia. The same year, he appeared as a bicycle dealer in the Anders Thomas Jensen written and directed Danish action comedy film Riders of Justice for Nordisk Film. In 2021, he appeared as Pilot Selenov in the English-language period romantic drama Firebird, directed by Estonian Peeter Rebane, and filmed on location in Estonia.
In 2022, he had a small role as a reporter in the Estonian period sports drama Kalev, directed by Ove Musting.
Velberg has also worked as a voice actor, dubbing animated foreign films into the Estonian language. In 2018, he voiced the role of Héctor for the Estonian release of the 2017 American animated fantasy film Coco. In 2019, he was the voice of Kristoff for the Estonian release of the Walt Disney Animation Studios' animated musical fantasy film Frozen II.
