Applying Data Validation to all sheets

if the table is in the same cell locations on each sheet:

1) on your sheet that is already formatted, click the triangle on the top left hand corner of the sheet (between 'A' and '1') to highlight the whole sheet
2) click Home > Format Painter (icon of a paintbrush). Double click to keep it enabled (press Esc to cancel)
3) Open on one of the sheets you want to apply the formatting to, and click the triangle on top left hand corner

Note you can apply to multiple sheets at the same time by holding down Control and clicking the tabs for multiple sheets.