A lot of these abilities indicates a winged hero with some kind of a blade or sword as the weapon of choice. Well a Valkyrie pretty much fills this criteria.
According to Britannica,
Valkyrie in Norse mythology were any of a group of maidens who served the god Odin and were sent by him to the battlefields to choose the slain who were worthy of a place in Valhalla. These foreboders of war rode to the battlefield on horses, wearing helmets and shields; in some accounts, they flew through the air and sea. They were associated with fairness, brightness, and gold, as well as bloodshed.
He also theorized that Valkyrie might actually be ‘Freyja’ a goddess associated with love and war in Norse Mythology. He states that some unused voice lines of Mars also leads credence to this theory.
Mars is also a god of war (in Roman mythology), so this might actually be somewhat plausible. Especially considering the fact that the fourth line of the code consists of 'Freyrs_sword', which refers to Freyr i.e. Freyja's twin.
TI10 was scheduled to take place in Sweden (a Nordic country, with Norse culture). Since TI9 in China gave us Void Spirit, a hero based on Chinese mythology, revealing Valkyrie during TI10 might have been Valve’s plan.
TI10 was to be held from 18th to 23rd August 2020 at Stockholm, Sweden. However, in April 2020, Valve announced the postponement of the tournament. The company made this decision because of the global pandemics. The new date is unknown, however we do know that Valve is planning to host TI10 in 2021.
(Also Read: Valve Plans to Host The International 11 in 2022)
After the postponement of TI10 and the cancellation of the DPC 2019-20, Valve has not released any statement about the state of the Dota 2 esports scene. This has left many in the dark about the future of the Dota 2 esports scene.
Note: The images of Valkyrie used in this article are for descriptive purposes only and were not found in the Dota 2 files.