xdzt skribis:

perhaps 'senmojoseca'..?

Did you mean 'being boring'? Regarding the suggestion of senmojoseca itself, IMO it's all right, but it is worth bearing in mind that in Esperanto adjectives can be formed by just adding -a to a root, so you could also have just malmojosa or nemojosa etc. Again, if by lacking pizazz you mean something specific like lacking vigour, you could express that e.g. nevigla. A lack of flair or creative style might be senstila or sentalenta

"mojosa" is a monstrosity all by itself, but "senmojoseca" is much worse.

I like senstila.

Miland skribis:

xdzt skribis:

perhaps 'senmojoseca'..?

Did you mean 'being boring'? Regarding the suggestion of senmojoseca itself, IMO it's all right, but it is worth bearing in mind that in Esperanto adjectives can be formed by just adding -a to a root, so you could also have just malmojosa or nemojosa etc. Again, if by lacking pizazz you mean something specific like lacking vigour, you could express that e.g. nevigla. A lack of flair or creative style might be senstila or sentalenta

"Vervo" might do well for "pizzazz", at least in the sense of enthusiasm and vitality. But pizzazz, both as a word and a state of experience, is a little too Broadway to be associated with coolness.

As has already been mentioned in this thread, NPIV and Wells contain 'blabla!'. The dictionary by Kondratjev also has it. So, I've added to the Lernu dictionary:

blablai = to waffle on, to talk nonsense.
blabla! = blah blah

You can also find:

waffle = (food) vaflo; babiladi, blablai; frazumi
blah blah = blabla!, blablai

erinja skribis:

"mojosa" is a monstrosity all by itself, but "senmojoseca" is much worse.

I've translated 'cool' as 'malaĉa (or malaĉe)' after a recommend right here at this website. In its use of the negative and opposite, it's also vaguely similar to English usage of words like 'fat', 'bad', 'sick' and 'ill' to mean 'good', so I think it's very suitable.

What about "enui"?

"Via vesto estas enua kaj senstila." ŝi blablais al me.