Tryndamere needs rework in terms of his lore. His visuals and gameplay need to change.
There are many Ideas I have about him, and I like the characters' lore. However, his gameplay can be sometimes too useless or boring, he is mostly relied on auto attacks.
He should be the duelist but a skill maker, a champion who scales off the player's skills. When the player masters him, he will duel Fiora, Jax, Yi and the rest of the known duelist champions.
I just think he is too boring to play now because he is easy and ridiculously boring. Feels both useless and out of meta.