I agree. Animations always seem to look so ridiculous at first (I’m not calling yours ridiculous) , however (as with most things), a little patience, and a lot of practice can make your animations as pretty and neat as the second video you linked.
I unfortunately have not yet begun working on too many of the animations within my game. However, I have quite a bit of experience with 2D Animation, as well as a degree in Film Production and Digital Design, which I have made great use of while designing my game and the story/cutscenes within it.
To answer your question, I will attempt to give examples as to how your animation and the second animation differ, as well as offer simple tips that will go a long way towards helping you improve your own work.
The Golden Rule
One of the first and best pieces of advice I can give you is this. Study what you want to make. If you want a medieval fantasy sword fight, look up some videos on sword fighting techniques, watch films set in medieval periods, where the sword play is generally exaggerated while shooting, so as to make the scene more exciting. Even watching a single King Arthur film (“Tis but a scratch”) will improve your ability to visualize your animation. And this is just a specific example. Google is your best friend when it comes to studying through seeing. There are probably countless videos online made by sword fighting instructors that teach step by step and movement by movement how to do really realistic moves with any sword you can think to name. This even holds true for unrealistic movements such as the one in the second video, where physics don’t seem to dictate anything to the double longsword wielding man doing a nigh impossible helicopter move. Many animators/Filmmakers/Artists have created fantasy wire type fights, all searchable at the click of the mouse.
With that Golden Rule out of the way, allow me to engage your example.
Overall you have a pretty smooth animation, however I have yet to see a sword fight where a combatant doesn’t move their lower body at all. Think about the weight and lower body strength needed to maintain a perfectly still posture while waving a long blade as quickly and drastically as your character does. Try this out on your own with a wrapping paper tube. Imagine it is a sword and play pretend you are fighting with it. How do you move your body when swinging? What feels natural to your body, generally looks realistic as well.
Small Steps, but Plan Ahead
To create more realism, add some foot movement and positioning, starting with just your extremes (The first and final frames of the animation, the position you want your character to start their attack at and how you want them to look as they finish their swing), then the in-betweens ( the major points of contact with the body and ground) and then the filler (The movements in between the fillers to make the character move smoothly) You CAN do frame-by-frame animating (self explanatory name for moving your character in a progressive manner and animating them one frame at a time chronologically), however without a goal in mind or a concrete position to move to, it will become frustrating and difficult to make the animation seem realistic, and you may find yourself moving your character in weird positions that don’t really look good once you hit play. I enjoy how your character bounces lightly after each swing, as if they are ready for their next move, or a counterattack, yet again it seems odd if you don’t incorporate the legs. As this would mean they are stretching their torso up and down instead of bouncing on their feet.
The adage goes “Variety is the spice of life.” Now unless you are making a robot character who is designed to move in a robotic patterned repetitive manner, you are going to want to add some variety to your attacks. Currently you seem to have two swings, which are (as far as I can tell) the same pattern, in a reverse motion. This is fine, as it doesn’t look too ridiculous, however maybe a thrust, a jab, an upward slice, a horizontal slash, or other sword movements that I don’t know the proper names of, would create a cooler and more realistic feel to the combat. In the second example, there appears to be three distinct movements, all similar (slashing horizontally forward and to the character’s left, yet they also change in which arm does the slashing, the foot placement and body movement, and speed/energy of each swing. The first two seem to be light general hits, which combo into the third heavy helicopter slash). Add some spice into your art. Make it interesting and each move just unique enough to not seem robotic.
Combos and Game Combat System Design
On the topic of combos, choice is a big thing in fighting games. People enjoy having multiple methods of attacking and combo-ing movements (WASD) with attacks, but making the animation and thus attack pattern different depending on the combination of keys, is a huge draw. Just look at some of your favorite games which have combat. Or for that matter figher games solely devoted to combat. They rely on multiple combo moves and player input combinations to make the gam interesting.
Further remarks and Final Analysis
In terms of look. You also have to realize that your clip is a single animation or two being played in an empty environment, your model is still just made of basic parts, and no effects (particle emitters, which leave that shadow clone look on the second clip as the blade travels through the air, or sounds signifying the attack is happening, or environment to add more realism to the fighting itself) There is a bunch of other factors in animating then the primary character/movements. Even in one character blank background animations, the lack of other things and the way that character interacts with the non existence of everything else, is integral to achieving the desired effect.
As to other Roblox specific animations. I can strongly suggest reading up on the Animation Tutorials osted in Community Tutorials, and try looking for a plugin that is highly rated and recommended for animating. Roblox Studio is amazing, but the people who work tirelessly to create plugins which make other dev’s lives easier are the true heroes. The realism of your model all comes down to detail. The more detail you can fit in a space, the better it looks. Last but not least, study and absorb real world or cinematic examples, or tutorials. These will greatly improve your visualization of how you want your own character to move.
I recommend searching up the 12 principles of animation, simple things such as action reaction, anticipation, and rule of arcs can greatly improve your work. I hope this has been enlightening to a point. Good luck on your journey.