As you see here:
Total beats are 64 (instead of metric 64 + file 63 + winlog 1 = 128), so only the newest half of all beats are shown in the list (see 1-20 of 64, I would expect 1-20 of 128).
Moreover the list is fluctuating over time: sometimes 60 file- and 4 metricbeats are shown 5 minutes later it is vice versa.
Even if you use 'Filter beats' to show only e.q. metricbeats the number of really shown metricbeats vary from 0 to 64.
My recommendation is to extend the list that all beats can fit into it.