Time would have mechanics related to the temporal position and duration of objects (cards, draws, creatures, permanents, ...)
Time could:
change the temporal position
(present or past/future in various displacements from the present) changed to (present or past/future in various displacements from the present)
[Ex. Rewind: Changing a creature's drawing/summoning from past to the near future, Hasten: Moving a draw from the near future to the present]
use the temporal position as an input
[none yet]
change the duration
[none yet]
use the duration as an input
[Sundial kinda but mostly not yet]