I have sleeved my cards several times - all cards are the same size. Nothing fancy here: the size is 2.5 x 3.5 inches (or 63 x 88mm). This is generally called 'poker' size I think.
The count of cards:
233 Clue Cards (you likely don't need to sleeve these).
45 Lead Cards
20 Plot Twist Cards
8 Detective Cards
4 Reference Cards
310 Cards Total
And it's now added to the sleeves list. Thanks for the information.