According to Indiana DOR website (https://www.in.gov/dor/files/ib117.pdf), Indiana local tax and Indiana state tax use the same exemptions filed on form WH-4 to calculate taxable income.
For one-time or non-periodic payments, such as a bonus check, withholding should be computed without exemptions. 
On form WH-4:
Line 5: Total Exemptions ($1000 per exemption per year)
Line 6: Additional dependent Exemption ($1500 per additional exemption per year)
Line 7: First-time Additional dependent Exemption ($1500 per additional exemption per year)
Line 8: Adopted child dependent Exemption ($3000 per exemption per year)
In HRMS, INSIT state tax code has break down for line 5, line 6+7  and line 8
but there is no break down for local tax codes.  The only exemption shows in local tax codes is line 5 - Number of exemptions.
Since each type of exemptions has different allowance amount, we cannot add all of those exemptions in one line for Indiana local taxes.
How do we set up Indiana local tax  to match with the allowances of IN state tax code INSIT so both of them have the same taxable income?
How do we set up both Indiana state and local taxes withholding so bonus check will have no exemption calculated, 

Here is an example from Indiana DOR website and images of HRMS INSIT and IN local tax.

An employee is paid a weekly salary of $800; they claim five personal exemptions and is subject to county tax at the rate of 0.01. They claim three additional dependent exemptions, one first-time additional dependent exemption, and two adopted child dependent exemptions. The taxable income of $473.08 is the amount on which state and county tax should be calculated. Equation Math Deduction Constant from Table A $96.15 Deduction Constant from Table B (additional dependent) +86.54 Deduction Constant from Table B (first-time additional dependent) +28.85 Deduction Constant from Table C (adopted dependent) +115.38 Total Deduction Constant $326.92 Gross Income $800.00 Total Deduction Constant -326.92 Taxable Income $473.08 State Tax to Withhold $473.08 x .03 = $14.19 County Tax to Withhold $473.08 x .01 = $4.73

The deduction constant tables on the next page have been developed to help calculate state and county income tax. These tables divide the dollar amount of the exemption/dependent exemption by the number of pay periods. This will determine the deduction constant or the dollar amount of the exemption you should deduct each pay period from the employee’s gross income. Note that these tables are provided for regular periodic payments for wages, salaries, and other compensation. For one-time or non-periodic payments, such as a bonus check, withholding should be computed without exemptions. For purposes of withholding, Indiana does not follow the allowance for no withholding permitted for federal purposes under IRC § 3402(n).