Al-Isra · Al-Kahf

Both end with giving glad tidings to the believers but 17:9 uses 'yubashiru' (indicative) while 18:2 uses 'yubashira' (subjunctive) — a single vowel difference in the verb form.

An-Nisa · Al-Isra

Both command worshipping Allah alone and treating parents with goodness (ihsan) — 4:36 says 'u'budu Allah wa la tushrikuu bihi... wa bil-walidayni ihsana' while 17:23 says 'alla ta'budu illa iyyahu wa bil-walidayni ihsana' with a different construction.

Al-Isra · Fussilat

Verbatim: 'when We bestow favor upon man, he turns away and withdraws to the side; and when evil touches him, he is in despair'; both observe human ingratitude and despair as a recurring flaw -- 17:83 in Al-Isra, 41:51 in Fussilat.

Al-An'am · Al-Isra

Both forbid killing children out of poverty but 6:151 says 'min imlaq' (from current poverty) while 17:31 says 'khashyata imlaq' (fearing future poverty) — a significant difference in meaning.

Al-An'am · Al-Isra

Both contain 'do not approach the orphan's property except in the best way until he reaches maturity'; 6:152 appears in a ten-command ethical list at the end of Al-An'am, 17:34 stands as a standalone injunction with the same wording.