Seeds are a derived character of the spermatophytes. All of the plants in this clade reproduce using seeds. However, embryo formation is also a trait of the spermatophytes. Do you think true water-conducting tissue is a derived character of either embryophytes or green algae?

Embryophyta is a clade within the Phragmoplastophyta, a larger clade that also includes several green algae groups. Embryophytes are the plants growing on land which include hornworts, liverworts, gymnosperms, flowering plants etc while green algae mostly thrive in aquatic environment.

The conduction of water requires vascular tissue called xylem. In green algae, it is not necessary to have water conducting tissue as the entire body is in contact with water. However in embryophytes, having a vascular tissue is an adaptation that ensures to provide water to the higher parts of the plant which is not directly in contact with the soil.