Where and how to sell circulating coins from different countries.

Hello! I have many coin duplicates from a lot of countries. Example, I have ordinary Mauritius coins with face value of £12.80 and weight about 1 kg. Is there any option to sell those coins for face value or, let's say - half of face value, somewhere in UK?

https://en.numista.com/catalogue/pieces1830.html

https://en.numista.com/catalogue/pieces1834.html

 Also I have circulating coins from Cuba, Brazil, etc and I would be happy to sell them for at least half of face value.

Can't you get it converted in some Currency Exchange Center?

When it comes to circulating coins, you should probably trade those that have low mintages or ones that have few owners on Numista. Mauritius coins are an example.

All circulating coins that I have are common, and I do not know if there is any currency exchange center in UK where I can exchange with coins. Probably I have to try to sell on eBay for person who are planning to go to Mauritius, Brazil soon and so on, ha ha.
 In any case, I found that some scrap dealers are buying euro coins, but not any some local foreign currency exchange centers looking only for notes - not coins at all.