u/Key-Experience-7877

as per my observation (i am from up and been to other states a lot)-

1. Madhya pradesh (strikingly similar to south and central up)

2. bihar (western bihar is very similar to east up although maithali isnt that big language in up)

3. Haryana (khadi boli and haryanvi would sound same to a someone who deosnt speak that language, language and landscape based similarities b/w west up and haryana are very noticeable)

4. Rajasthan (borderline districts b/w up and rajasthan hold cultural similarities, but similarities reduce as further west you go)

5. Uttarakhand (same logic as rajasthan but difference increases even sharply as you go north)

6. jharkhand. (may have ranked above uttarakhand but tribal populations and forest cover is much higher and barely shares a border)

7. Delhi (ncr region and linguistic factors)

7.Punjab ( in a wider linguistic factor, there are similarities in language and landscape)

8. Chattisgarh (may have ranked above punjab but landscape is quite different and way higher tribal population)

9. Himachal (shares border in one district probably linguistic similarities in some of it's southern districts)

10. Orrisa (barely any similarities but rest are even different)