The creators of Warhammer 40,000: Space Marine 2 have released a diary dedicated to the new Techmarine class:
This is a specialist in controlling enemies and zoning the map. His arsenal allows him to restrain both crowds of enemies and individual dangerous opponents, while his allies calmly deal damage. From a gameplay point of view, the Techmarine is a versatile fighter with a slight bias towards melee combat. Unlike the Bulwark class, which also keeps enemies at a distance, preventing them from damaging attacking classes, the Techmarine is more focused on putting pressure on enemies with area-of-effect melee attacks and medium-range firearms.
The Techmarine has a special "servo-cannon" ability - it unleashes a powerful volley on nearby enemies:
In addition, the Techmarine can detect and activate stationary "Tarantula" guns on levels. These will attack enemies until they run out of ammunition or are destroyed. A unique feature of the Techmarine is the integration of the servo-cannon during gun strikes. This provides greater freedom of movement compared to other classes during these actions: for example, you can perform melee attacks while applying a gun strike.
The developer diary of Warhammer 40,000: Space Marine 2 with a description of the Techmarine mechanics is available at the following link.
They also showed gameplay with the Omnissian axe (the weapon will only be available to the Techmarine).