This question is rather broad, because "natives" in regard to the Age of Discovery can really be used to refer to "anybody who isn't European." Within Mesoamerica, there are a few dramatic descriptions from the native perspective that I think resemble what you're looking for. For example, this description of a cannon was given by the Aztecs to the Tarascans after the former had encountered one close up:

They carry a thing that sounds like the clouds and gives a great thunderclap, and all those it touches it kills, so that it leaves no one, and [with it] they ruined us.

However, it may surprise you that these kinds of descriptions are fairly rare. Cannons are rather odd things that are difficult to describe if you've never seen one before, but most of the stuff the Spanish had wasn't that alien to the natives. More commonly native people would simply draw comparisons to things they were more familiar with. For example, horses are frequently referred to as large "deer," as that's a similar-looking animal that they were familiar with. Here's another account from the same document quoted above (the Relacion de Michoacan). This section describes a few Spaniards visiting the Tarascan capital and bringing a group of pigs with them (domestic pigs being something the natives have never seen before):

And they [natives] bought everything that the Spanish brought them, and they gave [the goods] to the [king], ten pigs and a dog, and they told him that the dog was to guard his wife. And they exchanged the cargo. The king gave them cloth and gourds and cuts of leather and the Spanish turned for Mexico. And when the king saw these pigs, he said: "What are these things? Are these rats that these people have brought me?" And taking it for an omen he ordered them and the dog killed, and taking them, they threw them into the fields.

The king's disgusted reaction to seeing pigs is because the closest animal to a pig in the region was a javalina, which the natives saw as akin to a rodent or pest. When they encountered pigs for the first time, saw them as larger versions of javalinas - and thus were in no way an appropriate gift for a diplomatic exchange. This is fairly typical of any descriptions given by natives in the region, they used familiar words to describe unfamiliar things. Large ships were called boats. The Aztecs called steel swords "tepuzmacquahuitl" which in their language means "Iron Macuahuitl" (a macuahuitl being an indigenous sword-like weapon). Aside from a few specific exceptions, the Europeans weren't carrying a bunch of stuff that totally perplexed the natives.

The same was also true in reverse; the Spanish (and other Europeans) used familiar words to describe unfamiliar things. While the natives called European swords "iron macuahuitl" the Spanish called the macuahuitl a "broad sword" made of wood and stone. The Relaciones Geograficas de las Diocesis de Michoacan includes numerous Spanish descriptions of local plants and animals. Among the gems: jaguars were called tigers, cougars were called lions, and coyotes were called jackals.

The Europeans also encountered some things for which they had no descriptions. For example, no European had seen rubber prior to the discovery of the Americas. Charles Mann (in 1493) gives this description of rubber taken from General and Natural History of the Indies (1535):

These balls jump much more than our hollow balls - by far - because even if they are only let slip from the hand to the ground, they rise much further than they started, and they make a jump, and then another and another, and many more, decreasing in height by itself, like hollow balls but more so.

So bottom line, both the natives and the Europeans were exposed to new things through the Columbian Exchange. While a few of these things were novel and defied easy description, most of the time people were able to make sense of them using the vocabulary and concepts that they already possessed.