The moment you open the can, the safe contents get exposed to the environment, and the same food safety rules apply as for freshly cooked food, which means no longer safe (not necessarily spoiled but certainly full of bacteria and fungi soon) after just a few hours.
To achieve a comparable long shelf life, the food in the cans would need to be treated the same way as it was previously during canning, i.e. heated up to a specific temperature for a certain amount of time. This is almost certainly not possible with the bags you are considering. They need to be food safe, withstand temperatures of around 120°C (and you need a pressure canner too) and keep their seal safely and reliably over time. I would expect them to mange neither.
Of course you could consider other methods like pasteurization, but that would probably require refrigeration and still not solve the issue of a safe seal.
If weight is that much of an issue, either buy the kind of food in ready-made pouches or carry the dry ingredients and cook them at your campsite.