Is there a block feature? I didn't see one in the controls in game.

Back for normal attacks. Crouch and back for low attacks. There was some special blocks too but I don't remember how those worked.

Ah ok so just moving back blocks, appreciate it!

If you hold back + 2 attack buttons at same you go into "Faultless Defense". It drains up your tension meter slowly while in use but in return you can protect yourself against much greater attacks and take less damage.

But yeah, just holding back works for most situations.

Paraphrasing/Snatching from Dustloop's GG Accent Core Web Encyclopedia, which has explanations that apply to #Reload despite being written for the latest release of GGXX, Accent Core.

There's also an advanced version of a standard block that is called Instant Block (or "Just Defend"). As it sounds, you wait until the last moment and press Back or Down-Back (for low attacks) just as an attack connects. This is signified by your fighter flashing white. Instant Block can also be performed while in the air against your opponent's air attack, but not against ground-based attacks, which is where Faultless Defense would apply instead.

The reward for accomplishing an Instant Block is that your fighter recovers much faster (that is, they'll be in less block stun for any IB'd move) and there will be less pushback on your fighter (a good or bad thing, depending on your position onscreen). Overall, it's definitely not easy to perform in the middle of a fight (knowledge of your opponent's attacks helps), but Instant Blocking is a great technique to give you the edge when properly learned.

From the same GGXX AC Web Encyclopedia is a section that goes into far more detail on Instant Blocking if you want to know more.