Ok, I think the following might do what you need. The drawback of this approach is that there will be an interval between each deployment as the subsequent build is executed. Is this acceptable?
Define a profile in each project with the same name (say "publish"). Within that profile you can define a configuration to use the antrun-plugin to deliver the files with FTP (see below).
In the parent project you'll have a modules element, defining each project as a module. If you run mvn install -P publish, each project will be built in turn with the publish profile enabled, and the final artifact published to the target during the install phase. If you need to deploy additional files, modify the include element accordingly.
Note the parameters for the FTP task have been set as properties, this allows them to be overridden from the command-line and/or inherited from the parent POM.
<profiles>
<profile>
<id>publish</id>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-antrun-plugin</artifactId>
<executions>
<execution>
<id>ftp</id>
<phase>install</phase>
<configuration>
<tasks>
<ftp action="send"
server="${ftp.host}" remotedir="${ftp.remotedir}"
userid="${ftp.userid}" password="${ftp.password}"
depends="${ftp.depends}" verbose="${ftp.verbose}">
<fileset dir="${project.build.directory}">
<include
name="${project.build.finalName}.${project.packaging}"/>
</fileset>
</ftp>
</tasks>
</configuration>
<goals>
<goal>run</goal>
</goals>
</execution>
</executions>
<dependencies>
<dependency>
<groupId>commons-net</groupId>
<artifactId>commons-net</artifactId>
<version>1.4.1</version>
</dependency>
<dependency>
<groupId>ant</groupId>
<artifactId>ant-commons-net</artifactId>
<version>1.6.5</version>
</dependency>
<dependency>
<groupId>ant</groupId>
<artifactId>ant-nodeps</artifactId>
<version>1.6.5</version>
</dependency>
</dependencies>
</plugin>
<properties>
<ftp.host>hostname</ftp.host>
<ftp.remotedir>/opt/path/to/install</ftp.remotedir>
<ftp.userid>user</ftp.userid>
<ftp.password>mypassword</ftp.password>
<ftp.depends>yes</ftp.depends>
<ftp.verbose>no</ftp.verbose>
</properties>
</profile>
</profiles>
Update: based on your comment: You could use the dependency plugin to download each dependency, except that a parent can't have a dependency on a child, and it will be built before the child. It would have to be another project. you also need to have somewhere the information for where to deploy them to. At the moment you have the target information in the individual projects so it isn't accessible in the deployer project.
Taking this approach, you can define multiple profiles in the new project, one for each artifact. Each profile defines a dependency:copy execution to obtain the jar and an antrun execution for one of the projects. Common configuration (such as the dependencies for the antrun plugin) can be pulled out of the profiles. Also be aware that the properties will be merged if you define multiple profiles, so yo may need to qualify them with the artifact name, for example ftp.artifact1.host.
<profiles>
<profile>
<id>deploy-artifact1</id>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>copy-dependency</id>
<phase>prepare-package</phase>
<goals>
<goal>copy</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>name.seller.rich</groupId>
<artifactId>artifact1</artifactId>
<version>1.0.0</version>
<type>jar</type>
<overWrite>false</overWrite>
</artifactItem>
</artifactItems>
<outputDirectory>${project.build.directory}/deploy-staging</outputDirectory>
<overWriteReleases>false</overWriteReleases>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-antrun-plugin</artifactId>
<executions>
<execution>
<id>ftp</id>
<phase>install</phase>
<configuration>
<tasks>
<ftp action="send"
server="${ftp.host}" remotedir="${ftp.remotedir}"
userid="${ftp.userid}" password="${ftp.password}"
depends="${ftp.depends}" verbose="${ftp.verbose}">
<fileset dir="${project.build.directory} includes="deploy-staging/"/>
</ftp>
</tasks>
</configuration>
<goals>
<goal>run</goal>
</goals>
</execution>
</executions>
</plugin>
<properties>
<!--if the properties differ between targets, qualify them with the artifact name-->
<ftp.host>hostname</ftp.host>
<ftp.remotedir>/opt/path/to/install</ftp.remotedir>
<ftp.userid>user</ftp.userid>
<ftp.password>mypassword</ftp.password>
<ftp.depends>yes</ftp.depends>
<ftp.verbose>no</ftp.verbose>
</properties>
</profile>
</profiles>