The articles you referenced are for QuickBooks Online FULL SERVICE payroll. Yes, the correct term for this is a contribution, but it is SET UP in the same place as a payroll deduction under QuickBooks Essentials payroll (as opposed to full service payroll). Full Service payroll is easy to set up this kind of contribution: just call the payroll people at QuickBooks and they set all of it up for you. QuickBooks Essential payroll you have to do the work yourself.

To set up a SARSEP payroll contribution in QBO Essentials payroll, the steps are as follows: Gear icon, payroll settings, on the top line that says setup click "Deductions" then where it says create deductions/company contributions, add a New Deduction/Contribution.

However, a SEP is NOT the same as a SARSEP (see IRS pub 560), and is UNSUPPORTED by QBO Essentials payroll (see this article here: <a rel="nofollow" target="_blank" href="https://community.intuit.com/articles/1437402">https://community.intuit.com/articles/1437402</a> ). A SARSEP can NOT be established after 1997, though contributions may still be made. A SEP IRA does NOT permit salary reductions to contribute to the SEP.

If the contribution was paid out to the employee through the SEP plan over the course of the year, of course there would be no liability at year's end. However, retirement is about 10 or 20 years away.  When setting up an asset account in QuickBooks ONLINE, of type banking, there is a subtype trust. For trust accounts, these are accounts set up on behalf of another party (not the company). Therefore, this seems the best account to use to take the SEP into consideration, since the SEP account is set up in the name of the business on behalf of the shareholder employee. The liability takes into consideration that the money in the SEP is owed to the shareholder employee ( to be withdrawn upon retirement).  

I have seen other answers on here that suggested to debit Retirement Expense, and credit Retirement Liability.