Court would not entertain compliant as it is no longer an offence 

If the chargesheet was filed at that time and case is still pending in court then court might punished you with sum amount of fine. But if after 2018 someone drag you with that crime which is not existing then you will not be charged and case will be withdrawn but only if you commit that crime after 2018. Before 2018 or in 2017 you you committed then there are chances of getting punishment. Decision will be taking by court. 

Please specify what was your act which was criminal till 2018 but was decriminalized in 2018..

In criminal case you can be charged. The limitation part is very narrow in criminal matters. Can only comment the exact status if I know the complete fact

If a FIR was registered at that time then the police would proceed wit filing of charge sheet on the basis of the FIR.

The supreme court has repealed the law subsequently, hence you may fight the case on merits  and as per the latest amendment implemented by supreme court in this regard, provided you receive summons from the trial court.

The crime was committed in 2017 when it was an offence. It is not an offence anymore but i am sorry but still you cannot escape conviction if the charges are proved because it was an offence then.

Hi

Certain offences such as Adultery (497IPC) , Unnatural offences (Section 377 IPC) have been declared as unconstitutional and as such the said SC Judgment operates retrospectively (i.e courts cannot prosecute a person who is facing trial for the offence which is no longer a crime).

It depends on the nature of offence and the wording of supreme court in its judgement declaring the law unconstitutional. 

Hope this information is useful. 

- If that offence has be removed from the criminal law after 2017 , then you cannot be charged for the said committed offence in 2017. 

- Further , other case on the same cause of action is not maintainable. 

no longer an offence then there is no question of charged.