You can lauch factorio without mods enabled, then enable the mods the server needs and connect without restarting factorio. The map will be downloaded, then an instant desync occurs (also showing 'Migrated content' on the client right before desync, if there is migrated content).
Steps to reproduce:
- Put the mods the multiplayer game needs in the mods folder
- Start factorio and disable at least one mod
- Restart factorio
- Enable the mods you disabled in step 2
- Join the multiplayer game --> instant desync