Try this machine applique technique that resembles hand stitching, the finished look is similar to hand-sewn applique where stitches are barely visible along the edges of the appliqué shapes.
Appliqué Tips, Tricks and Projects - WeAllSew
invisible applique by machine - 30 second short
Appliqué Tips, Tricks and Projects - WeAllSew
Application with open embroidery foot 20 » BERNINA Blog
Blanket Stitch Appliqué with BERNINA Open Embroidery Foot #20/20C/20D - WeAllSew
Application with open embroidery foot 20 » BERNINA Blog
Application with open embroidery foot 20 » BERNINA Blog
Mastering Needle Positions
Blanket Stitch Appliqué with BERNINA Open Embroidery Foot #20/20C/20D - WeAllSew
14 Inch Embossed Applique