Even in that/this era I still see him being eternally ageless as he'd be a God even back then, unless he relinquishes to be come human (like in MK11, depending on what ending to go with), making him no longer Lord Raiden, just Raiden.

Well Seeing How He Relinquished his powers to "Lord Liu Kang God of Fire" Im Assuming He Will Hold The Mantle of Earthrealm's Protector and Raiden Will be a younger version of himself as a Kombatant around same age as the great kung lao or Maybe a Mentor of The Great Kung Lao's Because The MKX Raiden Did Say That The Family Of Lao Gave Him That Statued Momento as a Gift. This/That Raiden May Have Been a Younger Non Immortalized Raiden if Im Looking at the Time Line Correctly. This Younger Raidden Could Have always Seen Lord Liu Kang God of Fire as Earthrealm's Protector Untill He Relinquished His Powers unto The ThunderGod.... Raiden May Have Been to The Great Kung Lao as Liu Kang was to The Regular Kung Lao But Hey Who Knows Maybe These 2 Kung Lao's have secretly always been The Same Guy and the family of Lao is a permanent staple in time because of these Events.

It Looks like Young Raiden is a Real thing after all. Im Usually Not The Type to say This BUT.... TOLD YUH SO!! Lol.

Young Raiden Confirmed!!

https://www.youtube.com/watch?v=B9Jmkoc6nm8&pp=ygUXbW9ydGFsIGtvbWJhdCAxIHRyYWlsZXI%3D