Thank you for your suggestion re Noto Sans. ↖︎ The screen shot ones are perfect.
I don't have a plain Noto Sans, only Zawgyi, Myanmar, Kannada, and Oriya with their bold, italic, etc. options. Which seems like lot of options but when I type in any of them the font reverts to Calibri, whether I start in a Noto Sans type or type in Calibri and then change to Noto Sans.
When typing in Calibri the accents (I didn't put any on ѳ) look like this (top line): 
If I type in Calibri, the select the word and change to Noto Sans Kannada, for example, the accents go higher (second line).
If putting in accents manually after having selected Noto Sans Kannada, I have to switch back to it after every letter from Arial, which is what it switches the accents to from the original Calibri.

If I select the letters and accents and switch from Calibri/Arial to Noto Sans Kannada, it will show Noto Sans Kannada in the font window, but the accents remain high and and to my (granted, tired by this point) eyes, no discernible difference in the letters.

Is there a way to use the Turkish undotted i and add an acute accent to make a key that looks like the US keyboard held i option #3 í ? Or add the held i option #3 character to a "Russian" keyboard?
Accented vowels were used for teaching elementary Russian in Soviet so-called "national" schools, and Russian language education is likely still offered in some of the former Republics. So I would think a pre-composed character would exist.
Thank you again.