I'm currently in Forge 1.14.4, and set the server to exactly that. The only mod loaded onto the server right now is Lucky Blocks, which probably means this isn't an overload error. The logs specifically say "[java.lang.ThreadGroup:uncaughtException:1052]: at net.minecraftforge.server.ServerMain$Runner.runLauncher(ServerMain.java:63)". This may help. This is the full log, https://mclo.gs/kg4A6mC.
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