The Shinwa Densetsu no Eiyuu no Isekaitan series apparently spans thirteen novels, but only the first of them appears to have been translated into English so far.
Simply speaking its a standard overpowered-protagonist isekai with above average world building and a mostly solid cast of characters. The main issue lies with that previous ‘mostly’. One character in particular is pretty terrible and, unfortunately, it just so happens to be the protagonist; he’s dumb. Really dumb. So dumb I almost stopped reading partway though on multiple occasions. And considering this is already his second time being summoned I have little hope he ever gets any better later in the series.
The Seventh Princess and The Reginnaglar Ceremony are the first two books in D.C. Haenlien‘s Adelheid series. A work they claim is a “Western Portal Fantasy”… which is either a shameless lie or an indicator of extreme ignorance.
What the series is, is a Japanese reincarnation isekai right down to the inexplicable cooking subfocus (explicitly featuring Japanese cuisine no less). There’s nothing ‘western’ about it and I strongly suspect ‘portal fantasy’ is just a nonsensical rebranding of the term isekai.
The author’s questionable attribution practices aside the novels themselves are in fact quite good. Solid world building, a varied cast of characters, and more or less believable event developments (on par with most ‘modern day conveniences get introduced to a fantasy world’ stories anyway). Only real issues at this point are some minor editing mistakes, the aforementioned inexplicable food focus, and the possibility that the modern day convenience angle gets too far out of hand.