Share local maven repository to agents in Jenkins Pipeline

I'm having hard problems with a Jenkinsfile with a Pipeline.

I have a master Jenkins which runs in a docker container and other Jenkins slaves, which are also docker containers and some are Virtual Machines (e.g., Windows 10).

I perform the code checkout from Git in the master as first stage and for the further stages.

A Stage name 'Build' performs the generation of maven artifacts. I use one docker image to build my project (based on Maven and Java 9) without sharing any volume across host and container. I pass the source code using the stash / unstash functions.I'm using also the maven-pipeline plugin and the option withMaven(mavenLocalRepo: '')

I'd like to share what I've built on one agent to other agents in a Test stage, but it looks like at this point, stashing of repository is not working (it says: 'no file to stash') and I cannot deploy to a central maven repository (I use Nexus), because there are many concurrent builds possible and the deploy could not be safe.

How can I solve this issue?

Example of pipeline:

pipeline{
  agent none
  stages{
    stage('Checkout Repository'){ 
      agent { node { label 'master' } }
      steps{
        checkout scm 
        stash includes: 'project/', name 'project'
      }
    }
    stage('Build'){
      agent { node { label 'docker-app-builder' } }
      steps{
        unstash "project"
        withMaven(mavenLocalRepo: ".repository"){ sh 'mvn clean install' }
        stash includes: ".repository", name "repository"
      }
    }
  }
  stage("Test){
    steps{
      parallel "docker slave": {
        node("docker-app-tester"){
          unstash "repository"
          unstash "project"
          withMaven(mavenLocalRepo: ".repository"){ ... }                
        }
      },
      "Windows Slave": {
         node("windows-tester"){
          unstash "repository"
          unstash "project"
          withMaven(mavenLocalRepo: ".repository"){ ... }                
        }
      }
    }
 }
}