So far our students have simply copied the exercises made with demo editor to moodle (copy-paste) and that way you can copy the whole answer (both text and mathematical notations) - not just one formula. These boxes are actually answer fields in our abitti-exams and each box has a separate editor that saves all content inside it as one answer. It works fine, the answers have mathematical notations in alt tag and the only "downside" is that the images use external urls like
https://math-demo.abitti.fi/math.svg?latex=x%3D%5Cfrac%7B-b%5Cpm%5Csqrt%7Bb%5E2-4ac%7D%7D%7B2a%7D
The svg images look pretty and are visible in editor:
copied from editor with CTRL C - CTRL VSo the easiest solution to use this editor in moodle could be a simple Atto plugin or TinyMCE plugin but world wide using one demo server might not be the best solution (like Forkosh servers using Mimetex and Mathtex in the past). On the other hand copying/sending code (or images) from moodle to a math editor outside moodle (in an iframe) is not the best option.
Answers in Abitti system can't containt html - only text, mathemal notations and images (screenshots) copied from other programs in the system (Libre Office, Geogebra, MarvinScetch, Calculator software,...) Because creating an abitti exam takes some work and playing with usb sticks I usually let students to use their computers and internet freely during lessons and sometimes ask them to save their work to moodle (instead of making homework to paper) to force everybody to practice the tools used in national exams.