I've read that multiple times (see comments for example articles), and many top aggressive players have played it, among them world champion Kasparov and (potentially future world champion) Nepo.
I am still surprised by this, as English games often tend to be the most positional struggles (especially if Black does not play e5).
Why does the English have this reputation, i.e. what are example games / variations that showcase the aggressive potential of the English opening?
One of the reasons mainline openings are "good" is that they are fundamentally strategically sound. You develop your pieces, fight for central control, secure your King, etc. All the things we are taught to do as beginners. Importantly, these are all the "prerequisites" for an attack (See The Art of Attack in Chess by Vukovic for more on this idea).
Is the English opening a better choice for attacking chess players than any other top tier opening? No. But is it fundamentally sound? Yes. Because of this, an aggressive player can choose variations that lead to more attacking chances.
Kasparov, who famously preferred active, aggressive play, played the English many times. Here's one fun example from him: https://www.chessgames.com/perl/chessgame?gid=1070502
If you are hoping for early tactics, sacrifices, etc. in wide open positions, the English isn't the best choice. But if you don't mind spending some time in the early stages of the game slowly building up the potential attack, it's a great opening.
Here are two more lesser-known examples of interesting attacks in the English:
It's worth noting that because the English usually doesn't lead to early clashes between the White and Black pieces, both sides can be flexible in choosing their setups. This means that if you're playing the English, you can opt for a line that tends to lead to more slow, strategic play, or you can go for a line that prepares for an eventual attack.
Your question asks for variations and that suggests to me that you are thinking along the wrong lines. Certainly there are very few, if any, followups to 1.c4 that lead quickly to sharp tactical play, which may be what comes to your mind when you see the word aggressive. You may be thinking of the numerous e4..e5 gambit lines with many checks and captures that often lead to level endings if both sides know their theory.
I think you would do well to read both those articles again, with an open mind. What both authors are telling you is that it is very hard against 1.c4 for Black to achieve early simplification. This does not mean that you will be able to gain an early initiative by tricky play. It does mean that by move 20 there are likely still to be a lot of pieces on the board and that the two sides have likely drawn up battle lines with conflicting objectives. That is a more realistic concept of aggression. It is an attitude that allows for both sides to show ambition, and aims to create situations in which the stronger fighter will win. I hope this makes sense to you.
