Closing in favor of this existing request: 

http://pricecharting.userecho.com/topics/169-chart-the-historic-prices-for-my-collection/

Please go there and cast a vote for this if you still want it.  Thank you.

We plan on adding these in the near future.

Which titles are we missing in Nintendo Switch?  I can definitely add them.

We are working to add this.  What should we consider an AES conversion?  Should that be an MVS or we trash that sale and don't track those?

Parasol Stars is a PAL game, like you said, I'm closing this request and you can vote for a the "Add PAL games" request if you want to up vote that one.

Slap Shot is listed on our site here:

https://www.pricecharting.com/game/sega-master-system/slap-shot

In the USA, American Baseball is called "Reggie Jackson Baseball".

https://www.pricecharting.com/game/sega-master-system/reggie-jackson-baseball

We don't track prices for European releases at this point so this is the best we can do for you right now. Thank you

This has been available for a while but this request was never closed.

You can see a feedback reputation score (overall), a reputation % (% of their transactions that are successful), and you can click on their feedback score to read individual feedback comments.

This is live and available for all sellers. Visit your settings page to go on vacation.

We have this on the site:

https://www.pricecharting.com/game/3689

Thank you