I've accidentally formatted my Transcend external hard drive. If there is a way I could retrieve some of it?
Yes, you can recover the drive content using the dedicated application developed by the Transcend for their products. The software name is actually RecoveRx and it available for downloading through the pages listed below.
Connect the device, install the software, select it and then follow the instructions. Depending on how much content you've had, it might take a while for the scan to complete.