Minis from the webmanga/anime Axis Powers Hetalia appear as a mochi representation of their Nation.
In Canon[]
Mochi Nations have their own spin-off series in the Hetalia canon. They are usually found with the Nation Estonia (or Eduard Von Bock). Aside from small gag strips, the only purpose of the Mochi are to be the Canon's mascots.
More on the Mochis and each nation's Mochi incarnation can be found here at the Kitayume Wiki.
Out of Canon[]
Mochi Nations in the Word Worlds, at the International Academy of Hetalia Fanfiction, and in the PPC are usually spawned with the misspelling of a Hetalia character's/a country's name. They eat bacon, raw eggs, fangirls, and lettuce. Their primary method of attack is blobbing, where they expand to thirty times their usual size and latch themselves onto the victim, wrapping them in a cocoon of rice paste and filling. The Mochi then either releases the traumatised victim, or bounces away with them.
Some Mochis, like the American ones, can sprout various appendages.
Mochis speak a mysterious language comprised mostly of "meeps", although words in English have also been appropriated and saddled with different meanings.
Creation[]
As stated before, Mochis are spawned with the misspelling of a Hetalia character's name. This can be their country name or their human name, and can occur in different languages. Therefore, while Furansu is not a Mochi-spawning spelling since it is the Romanised spelling of 'France' in Japanese, Fransu is a misspelling and will cause a French mochi to sprout.
Human names, due to translations, may have alternate spellings (Bonnefoy/Bonnefois, Lorinatis/Laurinaitis, Tino/Timo, Natalia/Natalya/Nataliya, Beilschmidt/Weilschmidt). The rule of thumb is that if it's not commonly seen in other fanfics, not in common usage, and not spelt as such on a reliable source, it is probably a misspelling and will spawn a Mochi.
Country names, on the other hand, are easier to spot because they are standardised for each language. All misspelt World One country names will create Mochis. Sometimes even former countries will still spawn Mochis ('Venace', for example, is a misspelling of 'Venice', and Venice was featured once or twice in Hetalia during its time as an independent state. It therefore spawns Mochis). Well-known place names may also spawn Mochis, like Evrest (a Tibetan Mochi).
There have been historical-figure Mochi spawnings, although those are rare and usually only for common misspellings for historical characters in Hetalia, like Napolean for Napoleon.