Congratulations! 0_= Writing is hard, sticking to it even tougher. I'll do some feedback since I think I'm one of the first to reply. Take any advice you get on here with salt - if one person tells you something needs changing, it probably doesn't. If three or more people, or a majority, agree then it might be worth taking another look at.
To me it's distracting to use brackets/ underlined, not underlined etc to explain the language that each character speaks in. I can't remember it all, and it's a paragraph right at the beginning that'll put off many readers! I find it difficult to keep my mind on the story with so many {Est} etc brackets, and I struggle with all these rules. Perhaps mentioning the language once as part of the description ("they chatted to each other in X language" or "he whispered in Elfish and was met with blank stares") rather than referring to it with each line of dialogue might be an alternative if this is core to the plot. If not, consider cutting the system. Another option (more work) would be for each language to have a specific speech pattern (think Khajiit in Elder Scrolls, clips on YT of Khajiit dialogue will give you a sense of what I mean). That seems far more reader-friendly. Some people even use distinct fonts for languages which I think is a neat idea (though can look childish if done wrong).
I understand it might be tough to take this advice seeing as much of your work is based on making this unique language-in-brackets/italics/underlined system.
Like I said - get a consensus as to whether you want to keep that, and keep up the good work!
I originally used fonts as you say, I was forced to change to using tags because the fonts did not show up on the online version properly and also messed up the formatting. Yes fonts work a lot better and are less distracting but I cannot use fonts because of the way it all works online unfortunately. Speech patterns would be really, really time-consuming to add.
It is case of I can't use the ideal setup (fonts) and am forced to use an inferior method or abandon the idea altogether. Abandoning the idea altogether gets me into the whole 'everyone speaks common' trope I am trying to get away from. I didn't use tags because I chose to, I used tags because I was forced to by the system. It is matter now of there having to be an alternative that is clearly less bad enough to justify the time needed to edit the book.
To sum the system up to anyone else who might turn up, I use
bold when a person is not speaking their own language. Rarely I don't translate at all, in which case I use
underline, usually because what they are *really* saying is important. A lot of the time people are just thinking, which is
italic, people usually
think in their own language even if they
speak a foreign language.