The verdict

CPU
Beelink SER5 MAX has 3.8x the CPU throughput (20,474 vs 5,333 PassMark).
Plex
Aoostar WTR Pro N100 transcodes more 4K HDR streams (~5 vs ~3).
Idle power
Beelink SER5 MAX idles lower (10W vs 15W) - cheaper to run 24/7.
Networking
Aoostar WTR Pro N100 has more NICs (2 vs 1) - better for a firewall or VLAN trunk.
RAM ceiling
Beelink SER5 MAX takes more RAM (64GB vs 32GB).

Which wins for each job

Job Aoostar WTR Pro N100 Beelink SER5 MAX
Plex / Jellyfin ~5 streams win ~3 streams
Frigate NVR ~4 cameras win add a detector
Proxmox / VMs 5,333 PassMark 20,474 PassMark win
Firewall / router 2 NICs win 1 NICs
Local AI / LLM no slot no slot

Approximate - capacity estimates from curated specs, the same logic as the recommender. Verify against your exact setup. Prices move; check the retailer.

Full specs

Spec Aoostar WTR Pro N100 Beelink SER5 MAX
Price (list) $279 $279
CPU Intel Processor N100 AMD Ryzen 7 5800H
Cores / threads 4 8
PassMark 5,333 20,474
iGPU Intel UHD Radeon Vega 8
NICs 2 1
NIC model Intel I226-V Realtek 1GbE
RAM max (GB) 32 64
M.2 free 0 0
PCIe slot none none
Idle (W) 15 10
TDP (W) 6 54