Unfortunately, you cannot change the font size of the barcode in the Ptouch Editor application.
However, for some barcodes you have an option to increase or decrease the barcode size under the Setup tab.
1. Open P-Touch Editor application
2. Click Insert menu => Barcode => Protocol tab to select your Barcode type
3. Click Setup tab, under Width, you can select the Barcode size
La version française sera disponible sous peu / The French version will become available shortly