[name_m]Hi[/name_m] Berries,
For the last year I noticed that many short boy names ending in “o” are getting a lot of attention, like [name_u]Leo[/name_u], [name_u]Theo[/name_u], [name_m]Hugo[/name_m] and [name_u]Milo[/name_u].
Which is your favorite and why?
[name_f]Do[/name_f] you think they’re timeless classics or that they will loose their appeal after some time?
They are definitely all classics. However I wouldn’t call them timeless classics because they have not been consistently popular forever- they are names that were once popular, then became dated, and are now becoming stylish again. Because of this I do think they will be considered dated again eventually. Leo and Theo will likely become dad and then grandpa names at some point, but then will likely come back into style a few generations later!
My favorites are Hugo, Leo, Otto, and Bruno
i have such a crush on names like this! i think i just love the letter “o”.
to answer my favorite is so hard, because i’ve considered so many of them. but my longest love is milo. i’ve always thought it was so sweet for a little boy, and i love it’s two meanings of “soldier” and “merciful”.
my other favorites are jago, leo, hugo, and otto 
[name_m]Sholto[/name_m] 
so rugged yet gentle, earthy and interesting!! [name_m]Otto[/name_m] would be my second choice-elegant and gentle!
I think they’ve been popular for a long time so I don’t think they’ll go out of fashion
[name_f]My[/name_f] favourite is [name_m]Elio[/name_m] but I love [name_m]Hugo[/name_m], [name_u]Milo[/name_u], [name_m]Otto[/name_m] and [name_m]Miro[/name_m] as well. I also like [name_u]Leo[/name_u] and [name_u]Theo[/name_u].
I think they’re timeless but it’s certainly the case that they are having a bit of a moment currently. In saying that, it’s not like they’re new names; they’re classics that have been used for centuries and beyond (in some cases). I truly don’t think they’ll go out of fashion or will be considered dated in the future.
[name_u]Leo[/name_u] will always be my preference out of these names since it carries sentimental familial ties with it but it is also beautiful and strong.
Besides [name_u]Leo[/name_u] I really am drawn to [name_m]Elio[/name_m], [name_m]Aurelio[/name_m], [name_m]Aero[/name_m], [name_m]Ezio[/name_m], [name_m]Eliseo[/name_m], [name_m]Enzo[/name_m], [name_m]Aridio[/name_m], [name_m]Franco[/name_m], [name_m]Gino[/name_m], [name_m]Viggo[/name_m], [name_m]Inigo[/name_m], [name_m]Laszlo[/name_m], [name_m]Sandro[/name_m], [name_m]Ivo[/name_m], [name_m]Miro[/name_m], [name_m]Pietro[/name_m], [name_u]Rio[/name_u], and an alternate spelling for [name_u]Leo[/name_u] - [name_m]Lio[/name_m]
[name_m]Elio[/name_m]
[name_m]Ivo[/name_m]
[name_u]Milo[/name_u]
[name_u]Leo[/name_u]
Definitely agree with pp’s about Hugo; I also like Enzo, Mako, Nico, Aiko, Toklo, Piero, & Eneko
I think timelessness really depends on the name— Hugo & Theo I can see as timeless classics— and Leo as a more modern but timeless name— though Milo is more modern and may eventually lose it’s appeal imo.
[name_m]Hugo[/name_m] is a top contender for our future child. I love that it has a more old-fashioned and timeless feel to it, but fits in with other names similar to those you’ve listed. It’s much shorter than I usually like for first names, but I’m just drawn to it.
Rio is my ultimate favorite, it means river in Spanish. One of my favorite artists just named his son this, so I truly hope it doesn’t sky rocket… 
I love that Elio means “sun” in Spanish, it could also be a nickname for another favorite of mine, Emilio.
Other favorites include, Enzo, Lienzo, & Milo
my fav name ever is rio 
i also love leo (was my first love! i’ll always like him :)), cosmo, elio & caio!
Hugo! Timeless classic is the perfect description.
[name_f]My[/name_f] favorite is [name_u]Leo[/name_u] for no reason in particular. I just really like it!
I think these names are very trendy and likely to become dated, but I still like many of them. And they are all legitimate names with history so I don’t think they’ll ever be ridiculous, just probably less common.
[name_f]My[/name_f] favorites are [name_u]Arlo[/name_u] and [name_u]Nico[/name_u].
I love [name_u]Nico[/name_u] and [name_m]Hugo[/name_m] and [name_u]Leo[/name_u], recently I’ve been feeling [name_m]Viggo[/name_m] a lot.
I feel like names ending in o is a wide enough category that even though some will go out of fashion and become dated others will stick around and become new classics.
Those are my top 3. But I also like [name_m]Jago[/name_m], [name_m]Cosmo[/name_m], [name_m]Otto[/name_m], [name_u]Rocco[/name_u], [name_m]Elio[/name_m], [name_m]Enzo[/name_m], [name_m]Hugo[/name_m], [name_u]Milo[/name_u], [name_u]Leo[/name_u], Diego…
I think they’re a sort of “trendy classics”. [name_u]Theo[/name_u] is super popular right now because it’s short, bold and fresh but [name_m]Theodore[/name_m] has been a classic for ages. Same with [name_u]Leo[/name_u] (Leonard) or [name_u]Nico[/name_u] (Nicholas).
There are also those “international sounding” like [name_m]Bruno[/name_m], [name_m]Hugo[/name_m] or [name_u]Milo[/name_u]. They’re becoming very popular in several european countries.
[name_f]My[/name_f] faves are [name_m]Ivo[/name_m], [name_m]Otto[/name_m] and [name_m]Jago[/name_m], but I love the O ending sound and have a ton of other favourites too.
I think how traditional/classic they feel depends on the name itself – [name_m]Hugo[/name_m] and [name_u]Leo[/name_u] feel fairly classic to me, whereas [name_m]Oslo[/name_m] or [name_m]Kenzo[/name_m] feel pretty modern.
However, I do agree that this category as a whole is trending right now and will probably fall out of favour again at some point (before cycling back into style later!)
I like:
Another shout out for [name_m]Otto[/name_m]!
Also:
[name_m]Laszlo[/name_m] / [name_m]Lazlo[/name_m]
[name_m]Aero[/name_m] / [name_m]Eero[/name_m]
[name_u]Rocco[/name_u]
[name_m]Inigo[/name_m]
[name_m]Nero[/name_m]
[name_m]Oslo[/name_m]
[name_m]Franco[/name_m]
[name_m]Vito[/name_m]
[name_m]Kelso[/name_m]
[name_m]Cidro[/name_m]
[name_u]Fargo[/name_u]
[name_m]Pluto[/name_m]
[name_m]Marco[/name_m]
[name_m]Viggo[/name_m]
[name_m]Orso[/name_m] / [name_m]Urso[/name_m]
[name_u]Cato[/name_u]
[name_m]Rollo[/name_m]
[name_m]Thiago[/name_m] / [name_m]Tiago[/name_m]
[name_m]Lito[/name_m]
[name_m]Aldo[/name_m]
[name_m]Pavlo[/name_m]
[name_m]Gino[/name_m]
I agree with you, some of these names feel modern, other are vintage, and some are classics. It depends on where you live also. For example, [name_u]Leo[/name_u] is vintage in my area, [name_u]Theo[/name_u] is modern, and [name_m]Hugo[/name_m] is classic. [name_u]Milo[/name_u] is uncommon, but definitely rising.