She tries to look too young for her age. It's kind of cringy.
She doesn't dress very appropriately for her age. It's a little embarrassing.
この場合、次のような言い方ができますよ。
ーShe tries to look too young for her age. It's kind of cringy.
「彼女は若作りしすぎでちょっとイタい」
to try to look too young for one's age「年齢よりずっと若く見せようとする」=「若作りし過ぎる」と言えます。
ここの「イタい」は cringy を使って言うと良いでしょう。
ーShe doesn't dress very appropriately for her age. It's a little embarrassing.
「彼女は若作りしていてちょっとイタい」
doesn't dress very appropriately for one's age「全く年齢に相応しい格好をしない」を使っても表現できます。
embarrassing でもこの「イタい」を表現できますよ。
ご参考まで!