As far as I can tell swingthroughgrass-1.14.4-1.3.2 does nothing - I am not able to swing through grass when mobs are in the grass.

Forge 1.14.4-28.1.56

Checked on forge 1.14.4-28.1.61 clean install with only this mod. I am able to kill mobs through grass. Do you have more info? Maybe multimod interaction issue?

Oh, my bad. I'll try to find the conflict :)

So I found the issue - I'm not too bright. I removed it from the server weeks ago in the thought that it was client-side only. Sorry for taking your time.

Swing Through Grass works perfectly fine in Singleplayer, but I cannot get it to work on servers.

well, I've checked multiplayer once again and it is working for me, so please provide more information like what exactly doesn't work, recording, logs, modlist (on client and server), etc