First of all, understand your accountant is probably only making recommendations based on what typical payroll software shows. Frequently, there are no legal requirements for content of payslips.
Second, understand that Manager makes no pretense of being a sophisticated payroll management package. It has basic capabilities suitable for many small businesses. If you need, under law, or desire all the information listed, particularly the year-to-date summaries every pay period, you would probably do better to purchase or subscribe to another payroll package or service.
Third, you can definitely perform (or have an external service perform) all the payroll and tax calculations outside Manager and enter summary transactions for each pay period. This has the advantage of transferring the burden of keeping up with changes in tax and reporting requirements to someone else. The disadvantage, of course, is extra cost. But many find the peace of mind worth it. If you go that route, you should get (or produce) reports summarizing the totals for various liabilities and expenses, which you would enter into Manager. You would need to create ordinary accounts that basically mimic the automatic ones involved when the Payslips tab is enabled. So, liability accounts to post amounts owed to outside entities for tax withholding, retirement contributions, and so forth. Expense accounts for posting wage and salary expenses.
It is really fairly straightforward, and your accountant can tell you what s(he) recommends. The important thing is not to use the built-in accounts for external payroll processing, because these are hard-coded to perform various functions you might not want.