Just as a FYI. A while back I tried to work on a DLL that would allow doing pretty much what you propose: replace mIRC's standard text strings with translations as taken from a file. I abandoned this project after reaching the conclusion that point #9 from Khaled's list (in the post maroon linked) really has to be resolved first: most of the text boxes in mIRC's dialogs are just big enough to fit the English text, and so any translation with wider text gets cut off. Either Khaled would first have to make a more "flexible" dialog system (which is probably a lot of work), or every translator would have to adjust the positions and sizes of all controls in all dialogs to make the translations fit (..a downright nightmare). I really do like the general idea of being able to translate parts of mIRC, and I don't think all of Khaled's points are needed to get useful results, but I guess my point here is that right now, it is not easy even to get something simple going.
Yes, you're right, it won't be easy to do. Probably need to set the maximum possible pixel width (with a margin for other longer texts) to edit text translation in dialog boxes for all options, and if the text does not fit within these boundaries, it will be automatically cropped. In turn, the authors of the translation will have to somehow adjust in order to meet these restrictions using abbreviations in the text. In any case, it will already be their own translation of the text and they will be able to decide how to do it correctly, so that it looks aesthetically pleasing and as clear as possible in their native language.
It might be another option if all dialog boxes with options were given the ability to resize, so that the width and height of the dialogs could easily be changed to the required dimensions to fit any long description.
Curious if you're planning to translate the documentation too? It's not always obvious what changes are made to the mirc.chm between versions, since it's not always having changes only for the new/updated commands/identifiers. And don't forget that there are some parts of the documentation that's only in version.txt
Most likely yes, I think that someday I could do translation for the accompanying help documentation "mirc.chm", but this is already a secondary issue and is more needed for advanced users who are involved in scripting. In addition, this can be done not for every new release of the client, but only when the most important and breaking changes are made.
According to my observations over the years, people have always encountered difficulties in setting up mIRC due to not knowing English, so I know for sure that people would like to get the client settings that are understandable in their language, which are located in options the client, even if for this they to them have to do everything on your own. In addition, the most successful text files with translation will later be distributed on the internet to users whose native language is different from English, and the most successful text translations in the future could be included and added to the "languages" folder in the official release of the mIRC client.