To reiterate, you’ve got 16 items that need to be done over the course of a week and you’ll be assigning 2 people to do these items at 100%. There also doesn’t appear to be a specific sequence for the items and the primary work volume on these 16 items can alternate.
Generally speaking, project management guidelines talk about keeping tasks within an “80 hour” rule. Stated another way, we want deliverables on at most, a 2 week cycle. There is however the other side of the equation which says don’t make the tasks so small that your schedule ends up with hundreds/thousands of tasks that are less than a day in duration. You’ll end up with a scheduling nightmare. So there’s a balance that you need to find. Is it worth spending a 3 days or a week trying to figure out how to set up your 16 items as 16 tasks, or is it easier to simply note that 40 hours is required for a block of 16 items which can be managed from a to-do list attached to the task?
As I’m sure you’re finding out, there’s a lot of complexity in setting up those 16 tasks, especially when the two assigned resources have vastly different work assignments on each. Without the right leveling options your schedule will most likely contain lots of non-working gaps. With the right leveling options, the gaps can be removed, but the result may be resource #1 working on items 1-3 while resource #2 is working on the only the first item.
So, based on what your describing, my recommendation is to keep it simple. On a piece of paper, a spreadsheet, whatever, map out the 16 items to be completed along with the work for each resource. Sum up the total resource estimates. Make allocation adjustments if needed. Meaning if resource #1 is allocated 68 hours of work to be completed in 5 days, that means that about 28 hours of that work should probably be shifted to resource #2. Basically, try to get the balance as close to 40 hours for each resource as possible. If both resources are somewhat balanced and both are well over 40 hours, then you have an expected duration problem. Assuming they are both 40 hours or less, add the task to the schedule with the refined allocations. Add a note to the tasks summarizing the 16 items this covers and the individual estimates to the schedule task.
Bottom line, ask yourself this. What is the driving reason that means I need to create these 16 work items as individual tasks? If there isn’t one, simplify.
Here is a link to a leveling article I wrote. https://www.mpug.com/articles/resource-leveling-resolution-options/
Look specifically at the section on “Leveling can adjust individual assignments on a task”. It provides examples of how MS Project can shift start dates of assigned resources or require that both are available before a task can be started.