[Takket]

Can someone list for me all the personnel (like Aquiel Uhnari) or other cards (like Secret Compartment) that can download artifacts without earning them from a mission solve?

No way to search for this ability.

[Boffo97]

There is a checkbox in the skills section that lets you search for special downloads. You can scan through the results list to check for any personnel that artifacts.

From my count:

Aquiel Uhnari Canar
James Tiberius Kirk Tantalus Field
DaiMon Bok Thought Maker
Leonardo da Vinci Mona Lisa
The Foragers Ophidian Cane

and Secret Compartment is the only non-personnel way of earning artifacts outside the normal way I know of.

[princedetenebres]

There's also the Amargosa Observatory that lets you get the Trilithium Weapon.

And Ferengi Commerce Operations, Raid Opposite Quadrant, as well as We Look For Things that also have the ability to get you an artifact under specific circumstances.

[Boffo97]

Oh well. At least my answer on personnel was right.

For now.