If you replace into with in, can a sentence change its meaning?
For example, are the two sentences below equivalent in meaning?
I placed the coin into her hand.
I placed the coin in her hand.
If you choose the right sentence, the meaning can indeed change.
I took the statue in the garden.
I took the statue into the garden.
In the first sentence, "in the garden" modifies statue, and specifies which statue you took. In the second, "into the garden" modifies "took", and specifies where you took the statue.
I detect little difference, and both are found. Just possibly, the first might emphasize the action, the second the resulting state.
A real case of ambiguity I have encountered was the following (written by a French person in a technical document):
The characters are then read into the buffer
This appears to mean "read from somewhere into the buffer".
In fact, the writer intended it to mean "read from the buffer".
I think an English writer would have said "from" or "out of", but "in" would still have been interpretable. "Into" actually made it mean the reverse of what was intended.
'In' emphasizes the fact it is in your hand, whereas 'into' emphasizes the movement of placing it there, that's why it is used with verbs of movement. To answer your question, I don't think there is a difference in meaning, the result is the same.
In general, the word "in" emphasizes the situation of something or someone being inside of something. For example: I am in the hostel. The eggs are in the refrigerator. There is a cat in my house.
Into emphasizes the action of a thing or a person entering or being put inside something. For example: I am walking into the hostel. He put the eggs into the refrigerator. I saw the cat running into my house.
So, to describe your location or the location of a thing, you say "in". To describe something or someone going inside another thing you say "into".