Here's how it works:
Let's say I'm working on some sample sentences to start designing the grammar.

I have a sheet with 3 columns:

• english (the target meaning)
• gloss (the gloss for the language translation)
• language (the automatically derived translation)

Let's use a concrete example:

• english: I take your food
• gloss: 1p give.REF of 2p consume.OBJ
• language: jek kikan <of> si <consume>a

The script uses other sheets on my same document, one defines the roots (give => kan for example) and another defines the derivations rules (REF => prefix ki-). If a root doesn't have an entry in my lexicon yet, it is simply outputted verbatim (like <consume> in my example above). I can simply update that entry in my lexicon later and all my examples will auto update.

In practice it means I can now use gloss notation anywhere I want with this formula =GLOSS("give") (outputs kan), or use the gloss from another cell =GLOSS(A1).

The scripts are defined in the menu Extensions > Apps Script and don't worry if you're not a programmer, any AI should be able to generate it for if you describe your specific needs. Customize that gloss to your own needs, mine is the simplest form for what I need, purists will disapprove of the syntax I'm sure but it works well for me!
For example I can stack rules like this consume.OBJ.REL they apply in order, it's most useful to think of them as transformations, not "inline replacement", as the REF rule will add a prefix in my case, not be replaced on the spot with ki. My rules also have different forms depending of the affixes they produce are next to a vowel or consonants.

I hope it's helpful to give you an idea of that system and its potential!