Contradicting laws
<p>If one law is valid in one jurisdiction say country A Wich says <em>you must use digital currency on Sundays</em>  and another law opposing that law is there in another jurdiction say country B which say <em>you must not use digital currency on Sundays</em>. A person sitting in one legislation has accepted that the laws of the other legislation applies to him via a contract ( many contracts say &quot;you subject yourself to the exclusive jurisdiction of the court of country B&quot;) or those laws apply because he trades (does business which involves a digital currency)  in those countries.What should he do use or not use digital currency on sundays?</p>

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<p>What should he do use or not use digital currency on sundays?</p>
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<p>If I understand correctly, you are asking about a scenario where the parties agree that the governing law will be that of jurisdiction <em>B</em> notwithstanding that the contract, or the relevant part thereof, will be performed in jurisdiction <em>A</em>.</p>
<p>If <em>A</em> and <em>B</em> were [in] different countries, the issue <em>could</em> depend on what (if any) international treaties binding both countries provide regarding a conflict of laws. Absent any realistic specifics (enasia and eukaria are not realistic), let's assume that <em>A</em> means <em>the U.S.</em> or is some jurisdiction in the U.S.</p>
<p>The contractually chosen law (jurisdiction <em>B</em>) would apply unless doing so contravenes policy restrictions of the jurisdiction where the contract is performed (jurisdiction <em>A</em>). Those policy restrictions could be public policy, legislation, or legislative intent that can be inferred from jurisdiction <em>A</em>'s laws. For instance, see <a href="https://www.leagle.com/decision/20011196265f3d93111109" rel="nofollow noreferrer"><em>Ticknor v. Choice Hotels Int'l, Inc.</em>, 265 F.3d 931, 937 (9th Cir. 2011)</a>:</p>
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<p>The law of the state chosen by the parties ... will be applied ...
unless ... application of the law of the chosen state would be
contrary to a fundamental policy of a state which has a materially
greater interest than the chosen state[.]</p>
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<p>(citing <em>Restatement (Second) of Conflict of Laws</em> at § 187(b)).</p>
<p>Note that discrepancies between <em>A</em>'s law and <em>B</em>'s law do not necessarily result in a material detriment to <em>A</em>'s policy, and it is unclear from your post whether refraining from using digital currency on Sundays would be such case. One would need to ascertain <em>A</em>'s public policy and/or legislative intent (if the relevant legislation has been enacted).</p>

jurisdiction