Texture size in game [resolved]

The textures are always made to fit the model, to make the sword bigger, you need to make a custom model, to do that you need a model creator, the one I use is Blockbench, this is the link: https://blockbench.net/ you can either download it or use the webapp.

Next you can use this guide to help you: https://podcrash.com/blog/how-to-use-blockbench-to-create-your-first-model/, after you've done that, click on Java block/item, name it and create the model and the texture, but make sure it's big, because you wanted it to be big, after that hover your mouse over file, then over export, and press Export block/item model.

Then choose where you want the file to be, go on MCreator, then click the button that looks like a Windows logo:

Then go to the area where you put the model, and double-click on it.

After that, got the item you want, and change the model to the one you made.

Then test it in-game!

Np