Hello. My name is Michael. I can help you with your question.
If you have the same font size selected, it is actually using that size. The difference is the relative size of the image. For example, a 10 point font on a small image will look very large. But on a big image, it may be barely visible. The font size is an absolute number. When you print - you may be printing out the same size print each time, but when you do, you may be stretching or shrinking the image to fit the page. But that will stretch or shrink both the image and the font.
The fonts will not change when they are transferred to a different folder. There is no way for this to happen. You said that the font sizes are tiny. The only way for the font size to be tiny if it is at the same setting as on another image is that the image sizes are different. You did not mention that the images themselves were the same size. Would you mind explaining a little bit more detail so that I can assist you? To images are not necessarily identical unless you're absolutely certain they are identical in size and resolution.