Numbering lists in paragraph options has the option of right-align numbers.
Is is possible in Indesign create a single style for this?
For the moment I am using 2 styles but in a large publication with many chapters is a hard labor the manual styling...
Or at least, how to identify them in the publication (footnotes with one digit + footnotes with two digits) to apply later the required styles?
I've done this with a decimal tab, though not with the hanging indent of your example. I've also used a right-aligned tab when there was no period. Either way, the tricky bit for me is getting the right spacing between the two tabs. I've even cheated occasionally with a figure space. However you go, you want to know in advance if you will need to accommodate 3-digit numbers.