new iPad 9.7 inch (2019) fit the 2018 Generation 6 cases?

The 9.7" iPad is not new for 2019. The only new models they released are the iPad Air 3 and iPad Mini 5. So you can shop for any case fitting the the 2017 or 2018 iPad.

Here is a link from Amazon with loads of options you can choose from: https://www.amazon.com/s?k=ipad+case+9.7&crid=1A68DDN7C4FC6&sprefix=ipad+case+%2Caps%2C175&ref=nb_sb_ss_i_3_10

Hello and welcome to Apple Support Communities sandywilder,

I see that you have a question about the compatibility of iPad cases. I'd be happy to get you pointed in the right direction for help with this.

The following link provides available cases for the iPad and which iPad they are compatible with.

iPad Accessories

Thank you for using Apple Support Communities.

You're welcome.