I'm a spanish speaker and recently I started a personal project of translating some comics, but now that I came across the word "knot" I'm not sure how to translate it.
I need help to find a translation for the words "knot" and "knotting" in spanish
Any suggestion is welcome

Could use "tie" or "tied". Scientifically it is called the "bulbus glandis", but wikipedia says the knot it's self can also be called a "bulb".
There isn't any Spanish translations of the page, but the Russian translation seems to keep the "bulb" terminology. I'll see if I can find it on another page (pretty sure the canid wiki pages specify it somewhere)

https://es.wikipedia.org/wiki/Canidae Says:

El pene de los cánidos macho está sostenido por un báculo y contiene una estructura llamada bulbus glandis, que crea un vínculo copulador que dura hasta una hora durante el apareamiento.

Which I'm not sure if provides contextual reference for translation, but hoping it does.

you could use nudo, but i think thats way too literal

I don't speak Spanish but this might also help.
https://es.m.wikipedia.org/wiki/Pene_canino