First, color or dye your eggs according to each fruit/veggie.
For a watermelon: Paint/dye your eggs in the darkest green and draw lines with a lighter green paint with a paint brush.
For a Strawberry: Paint/dye your eggs red and paint tiny spots of white paint. Cut out a flower from felt. (Like shown on the image- to form the strawberry).
For a carrot: Cut Strips of green felt and hot glue them to the tip of the egg.
For an eggplant: Cut another flower shape from felt to form the stem and hot glue to the egg.
For a pineapple: Cut out petals out of green felt just as shown on the image below. Cut a slit at the bottom of each the petal. Overlap the slit and glue together. Then glue the petal to the egg, overlapping each petal.
For a corn: Color the egg yellow. Cut out large slim petals of green felt to form the corn husks. Hot glue two or three husks to the eggs. Draw the corn kernels by making lines and drawing circles in between the lines.