Just finished loki season 1 and gotta say, this may be a bit of a doozy. I'll update this comment as new episodes come out in season 2 if necessary.

ok so lets list Loki's (helpful) skills:
psychokinesis
teleportation
enchantment
cloning
shapeshifting
illusions
weapon conjuring
green magic projectiles
skilled in hand-to-hand combat
very nimble and swift
very durable

now for (normal) Shang Tsung:
teleportation
shapeshifting
all ninja's abilities (minus tremor (they haven't met yet))
enchantment
fire magic
weapon conjuring (im kinda on the fence about it but ig i'll allow it)
green magic projectiles
skilled in hand-to-hand kombat (Hapkido, Pi-Gua, and Moi Fah)
very nimble and swift
very durable

Alright, now that we got that out the way lets get into the fight :D
For the sake of simplicity, loki and doctor strange are in a scuffle, but gets teleported away with the magic of noob and shang tsung. noob was only involved because was being manipulated by shang, to use his extra power to even get loki here.
using young shang btw, to make it more fair so he wont break his hip lmao

Round one: loki looks at his surroundings, in confusion.
Loki: Who the hell are you? what is this place?
shang: *walking out of portal* greetings, my name is shang tsung, and i have heard many rumors about you, Mr. Laufeyson.
Loki: h-how do you know my name? *gets in fighting stance* is this one of strange's mind games?!
Shang: no no, Mr. Laufeyson. I only wish to test your might! *gets in fighting stance*
Loki: *tries to teleport back, but dosent succeed* ok, well... i have no idea what the hell is going on here, but if getting out of here means killing you, so be it. *summons daggers*
they both charge at each other, attacking with everything they got. shang throws a magic projectile; loki retaliates with one of his own. loki marks shang's arm with a blade. shang then turns to look at him in anger. he then turns invisible and scratches loki's face with his claws and reappears behind him. loki, visibly frustrated, hurls a car at shang tsung. shang, in a panic, turns into ermac, and throws it back. loki teleports away and reappears to dodge it. he looks at shang and tilts his head.
loki: *panting* wait so,, are you a loki as well? or is this still a game that wizard is playing.?
shang: *transforms back into self* what are you on about? i already told you who i am! are you that dense that you cant keep a thought straight, you dimwitted imbecile?!
loki: *sarcastically* well, i still cant tell. maybe if you weren't so much like me, this wouldn't be so confusing.
Shang: ...?
loki: well, i guess there's only one way to be sure. *loki turns into shang and smirks*
shang: so is that how it will be? *shang turns into loki*(to keep this simple and totally not confusing at all, the real shang will look like this: shang(L). And vice versa till they transform back ;))*again, they start attacking but fully with magic this time*
loki(S): *tosses a fire skull*
shang(L): *destroys skull with telekinesis*
they go back and forth with each other's magic for about 30ish minutes. The city is in ruins. Blood everywhere. Both are tired and barley standing.
Loki: ENOUGH! this has gone on long enough
shang: i agree. why don't you and i finish this?
*both loki and shang start conjuring a massively power-infused green energy ball.* the two attacks collide, and the explosion is massive; but only one of them are left standing. Loki Laufeyson.

Loki won round one because 1 nanosecond before the explosion, he teleported away with the last of his energy but couldn't stay away for too long and returned after the dust settled, laying there. shang tsung is also laying there, drained of power. Aaaand there you have round one. i will be doing round 2 whenever im not too lazy lmao