As for referring to the book al-Mausu'ah al-Fiqhiyyah al-Kuwaitiyah, it explains that there are several scholars' views regarding the phenomenon of exchanging new money, namely:

ﺫﻫﺐ اﻟﺸﺎﻓﻌﻴﺔ ﻭاﻟﺤﻨﻔﻴﺔ - ﻋﺪا ﻣﺤﻤﺪ - ﻭاﻟﺤﻨﺎﺑﻠﺔ ﻓﻲ اﻟﻤﺸﻬﻮﺭ، ﻭﻫﻮ ﻗﻮﻝ اﻟﻘﺎﺿﻲ ﻓﻲ اﻟﺠﺎﻣﻊ ﻭاﺑﻦ ﻋﻘﻴﻞ ﻭاﻟﺸﻴﺮاﺯﻱ ﻭﺻﺎﺣﺐ اﻟﻤﺴﺘﻮﻋﺐ ﻭﻏﻴﺮﻫﻢ ﺇﻟﻰ: ﺃﻧﻪ ﻻ ﺭﺑﺎ ﻓﻲ ﻓﻠﻮﺱ ﻳﺘﻌﺎﻣﻞ ﺑﻬﺎ ﻋﺪﺩا ﻭﻟﻮ ﻛﺎﻧﺖ ﻧﺎﻓﻘﺔ؛ ﻟﺨﺮﻭﺟﻬﺎ ﻋﻦ اﻟﻜﻴﻞ ﻭاﻟﻮﺯﻥ، ﻭﻋﺪﻡ اﻟﻨﺺ ﻭاﻹﺟﻤﺎﻉ ﻓﻲ ﺫﻟﻚ ﻛﻤﺎ ﻗﺎﻝ اﻟﺒﻬﻮﺗﻲ؛ ﻭﻷﻥ ﻋﻠﺔ ﺣﺮﻣﺔ اﻟﺮﺑﺎ ﻓﻲ اﻟﺬﻫﺐ ﻭاﻟﻔﻀﺔ اﻟﺜﻤﻨﻴﺔ اﻟﻐﺎﻟﺒﺔ اﻟﺘﻲ يعبر ﻋﻨﻬﺎ - ﺃﻳﻀﺎ - ﺑﺟﻮﻫﺮﻳﺔ اﻷﺛﻤﺎﻥ، ﻭﻫﻲ ﻣﻨﺘﻔﻴﺔ ﻋﻦ اﻟﻔﻠﻮﺱ ﻭﺇﻥ ﺭاﺟﺖ، ﻛﻤﺎ ﻗﺎﻝ اﻟﺸﺎﻓﻌﻴﺔ.

ﻭاﻋﺘﺒﺮ اﻟﺸﺎﻓﻌﻴﺔ اﻟﻔﻠﻮﺱ ﻣﻦ اﻟﻌﺮﻭﺽ ﻭﺇﻥ ﻛﺎﻧﺖ ﻧﺎﻓﻘﺔ

Scholars of the Shafi'i and Hanafi schools of thought -except for Muhammad- as well as Hambali scholars in their well-known opinion, this is also the opinion of al-Qadhi in the book al-Jamik, Ibn Aqil and al-Syirazi and the owner of the book al-Mustau'ab, and others. That there is no usury in money that is made for transactions even though it is recognized as a transaction tool. Because money cannot be weighed and measured (like gold and silver), and there is no nash that states usury in money as stated by al-Buhuti. And also because the reason for the prohibition of usury in gold and silver is the price contained in both, namely the material of both is valuable. And this is not owned by money even though it is recognized as a transaction tool as stated by the scholars of the Shafi'i school of thought.

ﻭﻋﻠﻰ ﺫﻟﻚ ﻓﻴﺠﻮﺯ ﺑﻴﻊ اﻟﻔﻠﻮﺱ ﺑﻌﻀﻬﺎ ﺑﺒﻌﺾ ﻣﺘﻔﺎﺿﻼ، ﻛﻤﺎ ﻳﺠﻮﺯ ﺑﻴﻊ ﺑﻴﻀﺔ ﺑﺒﻴﻀﺘﻴﻦ، ﻭﺟﻮﺯﺓ ﺑﺠﻮﺯﺗﻴﻦ، ﻭﺳﻜﻴﻦ ﺑﺴﻜﻴﻨﻴﻦ، ﻭﻧﺤﻮ ﺫﻟﻚ ﺇﺫا ﻛﺎﻥ ﻳﺪا ﺑﻴﺪ

Therefore, it is permissible to sell money with each other unequally, just as it is permissible to sell one egg for two eggs, one coconut for two coconuts, one knife for two knives, and so on. As long as it's in cash.

ﻭﻗﺪ ﻓﺼﻞ اﻟﺤﻨﻔﻴﺔ ﻓﻲ اﻟﻤﻮﺿﻮﻉ ﻓﻘﺎﻟﻮا: ﻳﺠﻮﺯ ﺑﻴﻊ اﻟﻔﻠﺲ ﺑﺎﻟﻔﻠﺴﻴﻦ ﺑﺄﻋﻴﺎﻧﻬﻤﺎ ﻋﻨﺪ ﺃﺑﻲ ﺣﻨﻴﻔﺔ ﻭﺃﺑﻲ ﻳﻮﺳﻒ ﺇﺫا ﻟﻢ ﻳﻜﻦ ﻛﻼﻫﻤﺎ ﺃﻭ ﺃﺣﺪﻫﻤﺎ ﺩﻳﻨﺎ

The scholars of the Hanafi school of thought sort out this issue, they stated: it is permissible to sell one money for two money using the object directly according to Abu Hanifah and Abu Yusuf as long as both or one of them is not in the form of debt (must be in cash).

ﺫﻫﺐ اﻟﻤﺎﻟﻜﻴﺔ ﻓﻲ اﻟﺮاﺟﺢ ﻋﻨﺪﻫﻢ - ﻭﻫﻮ ﺭﻭاﻳﺔ ﻋﻨﺪ اﻟﺤﻨﺎﺑﻠﺔ، ﺟﺰﻡ ﺑﻬﺎ ﺃﺑﻮ اﻟﺨﻄﺎﺏ ﻓﻲ ﺧﻼﻓﻪ، ﻭﻫﻮ ﻗﻮﻝ ﻣﺤﻤﺪ ﻣﻦ اﻟﺤﻨﻔﻴﺔ - ﺇﻟﻰ: ﺃﻧﻪ ﻻ ﻳﺠﻮﺯ ﺑﻴﻊ اﻟﻔﻠﻮﺱ ﺑﻌﻀﻬﺎ ﺑﺒﻌﺾ ﻣﺘﻔﺎﺿﻼ ﻭﻻ ﻧﺴﺎء، ﻭﻻ ﺑﻴﻌﻬﺎ ﺑﺎﻟﺬﻫﺐ ﺃﻭ اﻟﻔﻀﺔ ﻧﺴﺎء

The scholars of the Maliki school of thought have differences of opinion but the strong opinion among them -which is also one narration of the Hambali scholars where the differences of opinion among the Hambali scholars were confirmed by Abu al-Khatib. This is also the opinion of Muhammad, a scholar of the Hanafi school of thought- that it is not permissible to sell money with each other unequally. And also not allowed on credit, and also not allowed to sell money for gold or silver on credit.

Based on the explanation above, it can be concluded that the law of exchanging new money on the side of the road is:

  1. Permitted. This is based on the Shafi'i and Hanafi schools of thought and the opinion in the Hambali school of thought. However, provided that the exchange of money is done in cash and not on credit.
  2. Not permitted. This is based on the strong opinion in the Maliki school of thought and some narrations in the Hambali school of thought.

That is the description of the law of exchanging new money based on the perspective of legislation and Islamic law.

References

Arifin, Zainal. “Pandangan Sejumlah Ulama Terkait Hukum Menukar Uang Baru.” 2022. https://jatim.nu.or.id/opini/pandangan-sejumlah-ulama-terkait-hukum-menukar-uang-baru-CvrMN

Arrahmah, Syifa. “Menukar Uang Baru Jelang Lebaran, Bagaimana Hukumnya?”. 2023. https://www.nu.or.id/nasional/menukar-uang-baru-jelang-lebaran-bagaimana-hukumnya-vzOe9

Oktavira, Aurelia Bernadetha. “Aturan Hukum Penukaran Uang Lebaran di Pinggir Jalan”. 2024. https://www.hukumonline.com/klinik/a/penukaran-uang-lebaran-lt55935fa4d11a1/