Subsequently in September 2019, Emma joined the ensemble at Theater Bonn. There she made a critically acclaimed debut as Octavian in "Der Rosenkavalier" by R. Strauss and Cherubino in "Le Nozze di Figaro" by Mozart. As the latter, she also made her debut on the main stage of The Royal Swedish Opera in Stockholm in February 2020. In October 2021, Emma made her debut in Vienna at Volksoper Wien where she, once again made a celebrated portrayal of Octavian. During the season 2021/2022, Emma was a part of the ensemble at Gärtnerplatztheater in Munich. There she performed roles such as Hänsel (Hänsel und Gretel), Niclausse (Hoffmanns Erzählungen), Orlovsky (Die Fledermaus), Olga (Eugen Onegin) and 2:nd Lady (Zauberflöte). In the fall of 2022 she was a part of director Amy Lane's acclaimed production of "Roméo et Juliette" at Malmö Opera, where she sang the role of Stéphano and in the spring of 2023 she sang the main character Adriana in the Swedish premiere of Kaija Saariahos "Adriana Mater" at Norrlandsoperan, a role which she also performed at Savonlinna Opera Festival in 2024.

As an opera singer, Emma has found a special interest in newly composed opera and has premiered several roles, including: Mezzo Soprano 1 in "Stabat Mater - a chamber opera" by F. Bayani Mabalot, Dalkullan Vera in "Det går an" by D. Fjällström at Läckö Castle, Ia in "Aquilegia" by G. Lindström at Sthlm New Opera and Miss Prism in the opera "The Importance of being Earnest" by B T. Andersson at the International Vadstena Academy and Stark in the childrens opera "Färden till Arareko" by Karin Rehnqvist. Emma has also premiered several concert pieces. Among them "Chapter one for Mezzosoprano" and "Den sista människans leende" by Ylva Fred and "Salve Regina" by Gustav Lindsten, the latter was performed during the play "The Tidings brought to Mary" at the Royal Dramatic Theatre in Stockholm in the spring 2018. 

Equally at home with oratorio and concert repertoar, Emma has performed with several major Symphony orchestras; The Stockholm Royal Symphony Orchestra, Malmö Symphony Orchestra, The Faroe Symphony Orchestra, Beethoven Orchestra Bonn, Aalborg Symphony Orchestra, Kristisansand Symphony Orchestra, Helsingborg Symphony Orchestra among others. She has sung the alto/mezzo-soprano solos in the Verdi "Requiem", Mozart "Requiem", "High Mass" by S-D. Sandström, "Stabat Mater" by G. Pergolesi, the "Matthäuspassion", "B minor mass" and "Weihnachtsoratorium" by J. S. Bach, Beethoven's 9:th Symphony and "Missa Solemnis", "Den heliga natten" by H. Rosenberg, "Stabat Mater" by A. Scarlatti, "Oratorio de Noël" by C. Saent-Saëns and "Messe pour deux voix" by C. Chaminade. With a great love for the lieder, she also performs in several Lieder recitals. She has recieved great praise when performing Alma Mahler's "7 Lieder" with the Norrlandsoperan Symphony Orchestra as well as Malmö Symphony Orchestra.

Emma Sventelius has had the great honour of being awarded several esteemed awards and scholarships over the years. Among them The Birgit Nilsson Scholarship in 2020. In 2019 Emma was awarded The Barbro Salén Scholarship at the Royal Swedish Opera and previous to that she received The Anders Wall Foundation's Giresta scholarship and The Vitaby scholarship from the OVIS foundation (2018), as well as the Joel Berglund-Foundation Scholarship by the Soloist of the Royal Opera in Stockholm (2015), the Aurora Lillieros Scholarship for singers (2016) and the Alvin's as well as the Larsèn-Todsen's scholarship from The Royal Swedish Academy of Music (2016 and 2017).