Use Repository Manager to proxy Gradle Central Plugin Repository

So I could use JCenter as the Plugin Repository proxy in my Nexus?
We are using Maven Central as the Maven Repository proxy.

Edit: Just made an attempt, but it could not find the plugins in JCenter

pluginManagement {
    repositories {
        maven {
            url "https://jcenter.bintray.com/"
        }
    }
}

It is only the plugins that are not official Gradle plugins that we are not getting when using Nexus.

plugins {
    id 'com.diffplug.gradle.spotless' version '3.26.0'
    id 'com.google.osdetector' version '1.6.2'
    id 'nebula.ospackage' version '8.0.3'
    id 'org.openjfx.javafxplugin' version '0.0.8'
    id 'org.beryx.runtime' version '1.8.0'
    id 'de.undercouch.download' version '4.0.1'
}

With the legacy plugin application one could specify the repository for these plugins in the buildscript section. However that does not work either, it still goes to gradle central plugin repository.
https://plugins.gradle.org/plugin/com.diffplug.gradle.spotless