Chains and Links
Chains
This game offers both Street Fighter style links and chains like Guilty Gear or the Marvel Versus Capcom style games. You can only chain weaker button normals into stronger ones, but you do not have to go in order. So you could go LP into MP into HP, or you could go LP straight into HP.
Another thing to note is that you can interchange punches and kicks, but you cannot chain a normal into the same strength, even if it's a different button. For example, you can chain LP into MK, but not MK into MP. Unless you have a the six chain gougi like in Double Face or Berserker deck.
On block, depending on the normals you press, whether the opponent is standing or not, and the timing of your button presses, the frame advantage will change. This is how you create a frame trap in FEXL, using delayed chains or certain normals in a chain to cause gaps and catch the opponent trying to challenge.
Links
Links in FEXL are meant more for punishes and causing bigger gaps in your pressure as most normals are unsafe on their own. It's the main reason chains are important to use so you can cause a true blockstring or pressure that has a tiny gap to make sure you aren't punished or easily checked.
To use links as in other fighting games, after a hitting a normal, you can link another normal regardless of what it is, so long as you have enough frame advantage. Using Kairi as an example, you can link his cr.MP into his cr.MK. Most of the cast can link those normals together.
Frame advantage does not change if you chain into a normal, so you can chain cr.LP, cr.MP, and still link into cr.MK.
Mixing chains and links are a core aspect of pressure in FEXL and it's usually best and safer to start with chains to condition the opponent, staggering chains, then mixing links into your chains. Since normals are quite universal there will be a lot of overlap once you get comfortable with this aspect.
Those coming from Street Fighter style games, you won't be seeing two quick light attacks into super often but that is applicable with crouching light kick into crouch medium kick chain. If done as fast as possible it will be a universal block string but using a link timed cr.LK into cr.MK will frame trap and work as a hit confirm into a special or super. It will also work as a common quick punish as well.
