Can a pharmacist replace Medikinet CR with Symkinet MR?

Yes, both medicines are the same form of modified-release hard capsules and your pharmacist can dispense Symkinet MR for Medikinet CR.
The difference is at the level of absorption - in Medikinet CR the second dose of the drug is released 4 hours after taking the capsule, in Symkinet MR - after about 4 hours. This may be a noticeable change for the patient, e.g. in the case of treating children - it is worth agreeing the change with the attending physician.

You can check availability and make a reservation here:

https://www.gdziepolek.pl/produkty/127637/symkinet-mr-kapsulki-o-zmodyfikowanym-uwalnianiu/apteki

In my case, after Medikinet CR, I had a very bad headache after 6-7 hours after taking it, after a week I gave up and returned to the same dose of Symkinet MR. The effect of both in me is similar at the dose of 40mg, as there was no focus. I'm still looking.

I was given Symkinet MR at the pharmacy as a replacement.
It seemed to me that the weaker effect was the nocebo effect, but from what I read, I am not alone. In my case, the noticeably shorter effect of Medikinet CR occurs if I take it without eating a SOLID meal (a sandwich or a bun is not enough).

I also agree with the negative answers, I feel a much weaker effect on the MR Symkinetic than I felt on the CR Medikinet. In addition, when I pour out a capsule, I see that there are much fewer granules than in a Medikinet capsule of the same dose.
Fortunately, the psychiatrist prescribed me only one package of Symkinet MR for a trial (the rest on the prescription I have on Medikinet).

I got Symkinet at the pharmacy for Medikinet, but it works differently. Firstly, it works less well, and secondly, I feel a lot of side effects, at the moment of "descending" I feel dizzy, I feel sick, I feel a huge sensory overload and irritation. I've never had such problems with Medikinet. I don't want to take this medication

I got symkinet MR as a substitute for Medikinet CR, due to the lack of availability in the pharmacy. I can't believe that anyone allowed it as a replacement. I don't feel any effect of the anxiety other than high-level irritation. I don't recommend it and I don't think symkinet should be allowed to be sold as a replacement.

It can't, if by some miracle there is a replacement then in the pharmacy they made a mistake. In some time it may be possible if the manufacturer provides more documentation because there is a difference in operation.

Difference in Operation:
I started taking Symkinet MR released as a replacement for Medikinet CR. In Symkinet, the second phase of release actually works. Early on telling the psychiatrist about how short Medikinet CR worked, he took it as a need to slightly increase the dose, or replace Medikinet with Concerta (which, however, he did not prescribe because it was very poorly available at the time).

To @Piotr:
I've contacted several pharmacists and indeed, opinions are divided. However, from a formal point of view, there are no contraindications to making the switch.

Since this is a new drug, and in addition, the difference in the level of absorption is described in the SmPC - there is no information from neurologists yet on how they treat this type of substitution.

I couldn't use a substitute at the pharmacy. I had Medikinet on my prescription, but the pharmacy didn't give me Symkinet.