问题：我是在docker-compose环境部署的

services:
  rabbitmq:
    image: rabbitmq:4.0-management
    restart: always
    container_name: rabbitmq
    ports:
      - 5672:5672
      - 15672:15672
    environment:
      RABBITMQ_DEFAULT_USER: rabbit
      RABBITMQ_DEFAULT_PASS: 123456
    volumes:
      - ./rabbitmq/data:/var/lib/rabbitmq
      - ./rabbitmq/conf:/etc/rabbitmq
      - ./rabbitmq/plugins/rabbitmq_delayed_message_exchange-3.13.0.ez:/plugins/rabbitmq_delayed_message_exchange-3.13.0.ez
    networks:
      pay_net:
        ipv4_address: ${PY_SUBNET_PREFIX}.15

插件地址：
https://github.com/rabbitmq/rabbitmq-delayed-message-exchange/releases

wget https://github.com/rabbitmq/rabbitmq-delayed-message-exchange/releases/download/v3.13.0/rabbitmq_delayed_message_exchange-3.13.0.ez

root@a5fd210b7eb1:/plugins# rabbitmq-plugins enable rabbitmq_delayed_message_exchange-3.13.0.ez
Enabling plugins on node rabbit@a5fd210b7eb1:
rabbitmq_delayed_message_exchange-3.13.0.ez
Error:
{:plugins_not_found, [:"rabbitmq_delayed_message_exchange-3.13.0.ez"]}

解决步骤：

1. 挂载进去后，到 rabbbitmq容器的 /opt/rabbitmq/sbin 目录下去
2. 执行./rabbitmq-plugins enable rabbitmq_delayed_message_exchange
   而不是./rabbitmq-plugins enable rabbitmq_delayed_message_exchange-3.13.0.ez

root@a5fd210b7eb1:/opt/rabbitmq/sbin# ./rabbitmq-plugins enable rabbitmq_delayed_message_exchange-3.13.0.ez
Enabling plugins on node rabbit@a5fd210b7eb1:
rabbitmq_delayed_message_exchange-3.13.0.ez
Error:
{:plugins_not_found, [:"rabbitmq_delayed_message_exchange-3.13.0.ez"]}
root@a5fd210b7eb1:/opt/rabbitmq/sbin# ./rabbitmq-plugins enable rabbitmq_delayed_message_exchange
Enabling plugins on node rabbit@a5fd210b7eb1:
rabbitmq_delayed_message_exchange
The following plugins have been configured:
  rabbitmq_delayed_message_exchange
Applying plugin configuration to rabbit@a5fd210b7eb1...
The following plugins have been enabled:
  rabbitmq_delayed_message_exchange

started 1 plugins.
root@a5fd210b7eb1:/opt/rabbitmq/sbin# pwd
/opt/rabbitmq/sbin

management

root@a5fd210b7eb1:/opt/rabbitmq/sbin# ./rabbitmq-plugins enable rabbitmq_management
Enabling plugins on node rabbit@a5fd210b7eb1:
rabbitmq_management
The following plugins have been configured:
  rabbitmq_delayed_message_exchange
  rabbitmq_management
  rabbitmq_management_agent
  rabbitmq_web_dispatch
Applying plugin configuration to rabbit@a5fd210b7eb1...
The following plugins have been enabled:
  rabbitmq_management
  rabbitmq_management_agent
  rabbitmq_web_dispatch

started 3 plugins.