To make a mirror image, we are going to use Google Drawings. Drawings is the unsung hero of Google Apps. With it, you can create drawings such as organizational charts or basic diagrams in which you need to include text, basic shapes, icons, and images.
To create our mirrored image, we will start by opening Google Drive, click New/More/Google Drawings.
To add text click Insert/Word Art
Create your Word Art and press return
You can change the size, color, and font of your Word Art by highlighting the text and choosing the settings you want
With your Word Art selected, click on Arrange/Rotate/Flip horizontally
You can also use the Arrange/Rotate/Flip horizontally feature with images.
Here's my flipped drawing before and after:You can now print your image to use as a transfer, or use it in a document.