A simple Time Freeze mod with theese features:

commands:
/TimeFreeze: Freeze time. if it was not frozen before.

/TimeUnfreeze: Unfreeze time. if it was frozen before.

/TimeFreezeImmune <targets (entities)> <immune (true, false)>: Set whether or not provided entities are immune to time freeze

/TimeManager: Open the manager gui.

Items:
Time Clock: a time clock that allows freezing and unfreezing time.

Gamerules:
timeFreezeAutoImmunePlayers (Time Freeze Auto Immune Players) <false>: whether or not allow players to always be immune to time freeze no matter if they are or are not on immunity list.

timeFreezeAutoImmuneAdmins (Time Freeze Auto Immune Admins) <false>: whether or not allow admins to always be immune to time freeze no matter if they are or are not on immunity list.

allowTimeClock (Allow Time Clock) <true>: whether or not to allow using the time clock. Commands not included.

timeClockImmunityManager (Time Clock Immunity Manager) <false>: Whether or not to show buttons to enable and disable Time Freeze Immunity

timeClockAutoImmuneTimeFreezer (Time Clock Auto Immune Time Freezer) <true>: Whether or not to make the user who froze time automatically imune.

showTimeNumberOnClock (Show Time Number On Clock) <true>: An Addition. that if enabled. will show the time in number on clock item.

showTimeFrozenOnClock (Show Time Frozen On Clock) <false>: An Addition. to whether or not. show if time is frozen on the clock.

Time Manager