At the moment Piktochart does not have a feature that permits you to copy a block in whole, but we can offer a workaround to copy objects or groups of objects from a single block and paste those on a different visual.
To do this, you will need to open your original visual into the Editor. Next, open a second browser tab and load Piktochart there, as well.
Choose the new template for your second visual and open it into Editing mode in the second browser tab.
On the original visual, click on a block to select it, and then press CTRL+A (or CMD+A for Mac users) to select all objects on the selected block. (You should be able to see a large square box surrounding the objects on the block, and several square shaped dotted lines for each object. This indicates that all of the objects are selected).
After selecting all objects on the block, press CTRL+C (or CMD+C for Mac users) to copy it.
Next, go to the visual in the second browser tab. You may create a new block or click to select an existing block. In this example, we will click the '+' button to create a new block.
Press CTRL+V (or CMD+V for Mac users) to paste all objects onto the block. All objects should then have the same position on the new block as they had on the original. You can move all of the objects at once by dragging the grouping on your new canvas.
If you want to have your new background the same color as your original's, you can find the original background's hex color in the Color Wheel there, then enter that same code for the background of your new visual's new block.