The wall bracket for the Sort and Go bin is available separately. Brabantia offers a wall bracket that has been specially developed for the Sort & Go series. This bracket is available in white and includes screws for mounting.
I can only tell you that the 17l bags do not fit this model. You can pull the bag halfway over the opening and then clamp it with the lid. But it's not really practical.
Only compost bins are odour-proof. Brabantia offers these two models: https://www.galaxus.ch/de/s2/producttype/abfalleimer-348?tagIds=41-832&bra=708&pdo=288-12425%3A1671 .
This model does not have an activated carbon filter and is therefore not suitable for storing green waste. Apart from that, I think the bucket is more or less odour-proof.
The 17-litre bag will certainly fit, but you are giving away 1 litre, as this product can only swallow 16 litres. I can't answer the other question. I would say it doesn't have a special device. You just have to put the rim over it.