Honestly, probably not much. None of these changes would happen overnight. Trade would be limited with Amerindian societies, since on Newfoundland they have all the furs, timber, walrus tusks, and anything else they need (except maybe thralls). Meanwhile, many local Amerindians are so poor that their societies risk becoming dependent on Norse trading posts where they almost require the Norse to procure basic goods like kettles and axes and knives. There is no incentive to learn how they're made. Fortunately, the alcohol in Norse society is far weaker than in Early Modern Europe.
Nor would they be immune to disease. They would not have the numbers capable of making the disease endemic, so they'd go from one disastrous epidemic to the next, although they would learn how to cope with novel diseases and would have partial immunity to some diseases. Unfortunately, Vinland is so remote from both Europe and Amerindian population centers that there aren't likely to be many diseases that make it over, let alone diseases that spread far and wide. Iceland did not have any major epidemics until the early 15th century for instance, and this epidemic (IIRC smallpox) killed about half the population.
The Norse are unlikely to sell the natives horses because those were very rare in Iceland and Greenland. Feral horses are more likely to be hunted and eaten by natives. Possibly sheep or cattle. The Navajo for instance took well to herding (mostly stolen) Spanish sheep. But these would be in less sedentary, more developed societies like the Iroquoian peoples, or the New England Algonquians once they become wealthier due to centuries of (mostly indirect) Norse trade.
The real gamechanger would be Norse exiles and adventurers. Vinland is too small to have a large number of these, and they'd be just as likely to go back to Greenland, Iceland, or Norway than go west or south. But they'd be present, along with no doubt Christian missionaries, so no doubt a Metis population along with Europeanised natives would emerge. This is where Norse traditions and tech stands an actual chance at spreading. Say a son of a Norse man and an Iroquoian woman sees his father's axe as he visits and asks how it's made, and the father decides to teach him what he knows about metalworking. Or a native girl is raised by a Norse family, converted to Christianity, and later marries a Norse trader who settles in her ancestral village. She might teach her daughters how to use a Norse-style loom (and her husband would know how to build one) which is more efficient than the looms used by indigenous societies.
But that takes some time to start happening and I think the biggest result is that the Iroquoian societies and northern New England ones are much wealthier and maybe a little more populous, with some social groups (from what I can tell, they'd probably form a single clan which would spread between different societies) using Christian symbolism and holding to a syncretic faith. But since this would take some time after the settlement of Vinland--2-300 years at least--it probably will still be spreading as the first Europeans show up.
I believe it was in Land of Ice and Mice where someone noted that Norse sheep and wool weaving techniques might have been useful to North American natives as a new source of fabric. I don't know much about Native American pre-Columbian textile work, but given the high cost of textiles in pre-industrial societies, a new introduction would presumably at least have a chance.
Shipbuilding technology is another interesting possibility- especially if the alt-North American seafarers discover the Grand Banks, bringing in a major new source of protein (in the form of seafood).
Writing is another frequently-cited technology that might have traveled with the Norse- although most of the population would have been illiterate, so the chances of crossing over to the native people is much lower than it might seem.
There was little need for additional protein in northeastern Indian societies--they had plenty in the form of shellfish, fish in general, and game. It was carbs and calories in general they lacked. Rye and barley might be viable, especially in areas that didn't/rarely grew corn like the Canadian Maritimes or northern New England in the early 2nd millennium. So animals, if present, would be more valuable as pack animals or for wool.
I think writing would spread but remain a closely guarded secret. The main forms of writing in Iceland and Vinland would be Bibles and messages using runes, many of which were ceremonial or cryptic in nature. So if they adopted runes, or used the concept to flesh out their native proto-writing, it would just be used to conceal knowledge like the Midewewin society did OTL with their proto-writing so not widely taught, known, or used.