Google Sheets Copy Conditional Formating to Multiple Cells

Select a cell with existing conditional formating applied, the copy the cell (Edit -> Copy).

Select a new cell or a range to cell to apply the conditional formating, the Right Click / Edit -> Paste Special -> Paste Conditional Formating only.

NOTE: Once the paste is done, you need to copy again before the next paste could be done.

NOTE: All the cells will share the same conditional formating. You can change the conditional formating (e.g. change text color) and it shall be applied to all cells with the same conditional formating.