Is there a shortcut to determine whether a transaction is accretive or dilutive to shareholders?

If the deal only involves cash and debt, you can simply sum up the foregone interest on cash and the interest expense on the debt and then compare it to the seller's pre-tax income. If the pre-tax income is higher, then the deal will be accretive to shareholder's. Note that in today's extremely low interest rate environment, it is extremely likely that the deal is accretive if it is paid for in cash/debt.

If the deal is an all-stock deal, then the shortcut is to see which company has a higher P/E multiple. If the buyer has a higher P/E multiple than the seller, then the deal will be accretive. If the buyer has a lower P/E, it will be dilutive.

If there is a mix between cash, debt, and stock, then there isn't a shortcut to determine whether the deal will be accretive or dilutive to shareholders.