Some packages versions are missing in oldstable (Tyche) so i can't install Stremio:
QuoteThe following packages have unmet dependencies:
stremio : Depends: libmpv1 (>= 0.27.2) but it is not going to be installed
Depends: qml-module-qt-labs-platform (>= 5.9.5) but it is not installable
Depends: qml-module-qtquick-controls (>= 5.9.5) but it is not going to be installed
Depends: qml-module-qtquick-dialogs (>= 5.9.5) but it is not going to be installed
Depends: qml-module-qtwebchannel (>= 5.9.5) but it is not going to be installed
Depends: qml-module-qtwebengine (>= 5.9.5) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
No missing, but the package developer supports newer platform than Debian oldstable.
Stremio can be installed on Debian Buster and newer only, sorry.
OK, there's an older version appimage, compatible with stretch at https://dl.strem.io/linux/v4.0.2/Stremio+4.0.2.appimage