However, the permlink format in WP Settings does NOT support regexp, at least not directly. You can however use rewrite tags, their definition DOES support regexp. There’s probably no reason to use custom rewrite tags, there’s a number of predefined tags available.

Regexps are very powerful. but not intuitive. I’ve found any one of the several regexp “fiddle” sites to be very helpful in composing a good regexp. Just one example is https://www.regexr.com/

But to get the rewrite rule to work what should i set the permalink to?

For example the page i have, that page get automatic a permlink. in this case. “serietabell”

But i want to use the url

https://www.wp.aktuellspeedway.se/sverige/elitserien/serietabell/2016/

and then i can’t find the page becasue obvious wordpress want me to use https://www.wp.aktuellspeedway.se/serietabell/

Te rewrite rule i use is
RewriteRule ^([a-zA-Z0-9\-]+)/([a-zA-Z0-9\-]+)/serietabell/([a-zA-Z0-9\-]+)/$ ?nation=$1&league=$2&season=$3

Is that because of some parameters in WP?

What i have now is

RewriteRule ^([a-zA-Z0-9\-]+)/([a-zA-Z0-9\-]+)/serietabell/([a-zA-Z0-9\-]+)/$ ?page_id=10&nation=$1&league=$2&season=$3 [R,L]

I Want to use for example > sverige/elitserien/serietabell/2016/ <

When i type this in the url now change to serietabell/?nation=sverige&league=elitserien&season=2016

serietabell/ is the permalink for the page in WP. But i want the url to still be > sverige/elitserien/serietabell/2016/ < and not being changed.