There were certain liberties used here. Obviously, Leroy's inclusion in the Tekken 3 storyline was major but there's more.
Right off the bat, there are cameos of Steve Fox, Craig Marduk and Feng Wei. They should had appeared later on. Also, we were shown Anna, Lei and Yoshimitsu.
@KasumiLover, you will be pissed as Anna hasn't have an actual role here, even with Nina participating front and center (in which I get with her in a sec). Marshall Law substituting for his son, Forest. We are also missing other Tekken 3 characters: Eddy, Bryan, Mokujin, Panda and Gun Jack.
Voices-wise (English dub), everyone was okay except for Heihachi's. They should've hired the guy who voiced him in Blood Vengeance or Street Fighter X Tekken because this one sounded
HORRIBLE.
The characters: Jin is way better here than the WTF? attempts/brooding personality after Tekken 5 onwards. He showed empathy towards others such as Leroy after their match and gave the winning money to King. However, you would see that when using the Kazama-ryu, he tend to "literally" followed his mother's footsteps (Thunder Fall Kick, anyone)?
Xiaoyu = lost her genki personality (and the obsession with Jin). Here, she is very spunky and sassy. Not to mention very powerful during her fight against Nina.
Then we have Hwoarang,. They showed the rivalry and both he and Jin had an official match but it's much more friendlier than the games. You literally see the friendship between him, Jin and Xiaoyu.
Speaking of Nina, they literally ignored her cryosleep amnesia plot from the 15 year time skip. Its like she's back in her T2 skipped to 5 onwards personality, ignoring the fact she's currently in her 40s. I'm disappointed about her fight with Xiaoyu, because they wanted Xiaoyu as the better skilled combatant against a very deadly assassin. Though King beated her later on.
Paul = the writers really want him to be the badass that the participants feared upon in the tournament and even gave him a cool personality. Heads up, he's not the finalist.
Jun = I liked that the writers gave her this warming personality and made her a very wise woman.
Julia = They went back to her original storyline, searching for Michelle and demanded Heihachi for the pendant back to her family. Speaking of the pendant, because it was a bit of a McGruffin, the writers wanted to make sure that the endings for Tekken 1 and 2 are canon in the following: Kazuya for 1, Heihachi (a bit) and Michelle's from 2 and Jin from 3. Heihachi revealed to hired thugs to search for Michelle's pendant in a lake.
Heihachi, oh boy. As much as I hated his voice, he was the antagonist here. Many characters stated to Jin that the Mishima Clan are evil. They even mentioned Kazuya being worse back during the events of Tekken 2. What made it worse is that Heihachi was responsible of unleashing Ogre to the world. So this basically retcon the original prologue of 3, when Heihachi send the Tekken Force to a Mexican temple and somehow Ogre attacked. Here, he unleashed Ogre that "killed" off most of the cast of Tekken 2: Jun, Baek, Wang, King 1 and Lee (doubt it, they would save that for possible Season 2) for the sake of getting rid of the Devil Gene. So, hearing that pissed off Jin at the end.
Bloodline, while had changes to make things current (technology is very current as viewers would see Jin on his cellphone and has "Beats-like" wireless headphones), did follow faithfully to the 15 year time skip between Tekken 2 and 3 and the 3rd tournament, for the part. The animations of the fight scenes which include the effects of the attacks are on point. Nipticks are those triangular shadows that appear on the characters that was used in Kengan Ashura, another anime that is on Netflix.
My gripe is that the team should not have started in Tekken 3. The reason why is because Tekken has much lore back in the day that it need to be shown and addressed it proper. Like with Street Fighter II (and how that ended "officially"), it is best to start from the beginning to know about Kazuya, Heihachi, the Mishima clan, the rest of the original fighters (Paul, Nina, Michelle, Anna, Lee, etc.) and how the King of Iron Fist tournament began and then jump to the events of Tekken 2 to see its proper resolution. Here, they started with Tekken 3 because it was the game that made and put the franchise on the map and had to include the well-known popular characters such as Jin, Xiaoyu and Ogre.
I'm hoping before jumping to the events of Tekken 4, the Bloodline team can go back to Tekken 1 and 2 so we can see the events on how the series first started.