The software you need!
As we went with Monogame as our Game Engine, we need a lot of external tools around it, as Monogame itself only comes with the MGCB-Editor as an image preprocessor.
To create graphics for our game, such as characters and levels, we searched for tools helping us create those.
For our character design and animation, we went with Aseprite as our Sprite-Editor, because it is fairly cheap (20 euros) and relatively straightforward. At the moment, we are running into compatibility issues on Linux, but we are looking forward to sorting those out by next week.
For our level-design, we aim to use Tilemaps as a construct for our levels. To design those, we want to use the
Tiled-Editor, as it is available for all main platforms and widely used as well.