There are several web novels that share some elements. 'Re:Zero − Starting Life in Another World' is somewhat similar in the sense that the main character is in an isekai setting. Although the character isn't a 'yankee' type, the theme of facing challenges and forming relationships in a new world is there. Also, 'Sword Art Online' has an element of being in a different world (virtual in this case) and dealing with different entities, which could be related to the overall theme of the given web novel.
I'm not entirely sure as I haven't read it specifically. But generally, in this kind of 'isekai' (another world) themed web novel, it might be about a 'yankee' (which could refer to a certain type of character, perhaps a tough or delinquent - like one) who gets transported to another world and is loved by spirits there.
Based on the title, one of the main characters is likely the 'yankee'. And the other important character would be the'seirei' (the spirit) who loves the Yankee in the isekai world. But there could be other supporting characters that we don't know about without reading the novel.
The title 'yankee wa isekai de seirei ni aisaremasu novel' gives some clues. 'Yankee' might be a unique type of protagonist. The 'isekai' part indicates a different world setting. And 'seirei ni aisaremasu' means being loved by a spirit. It could be a story about a Yankee's adventures in a new world where a spirit has special feelings for them. There could be elements of discovery, relationship - building between the Yankee and the spirit, and maybe challenges they face together in this strange new isekai world.
There are several works that share similarities. For instance, 'Re:Zero − Starting Life in Another World' has the concept of a character being in an isekai world and facing numerous challenges. The main character has to constantly adapt and find solutions, much like in 'isekai wa smartphone tomo ni web novel'. 'Grimgar of Fantasy and Ash' is also similar as it focuses on a group of characters in a new world trying to survive. And 'How a Realist Hero Rebuilt the Kingdom' where the protagonist uses his modern - day knowledge, somewhat like how the smartphone in the other work might provide useful knowledge, to make changes in the new isekai world.
One similar work could be 'KonoSuba'. It also has elements of being in a different world and the main characters have to deal with various challenges using their own unique skills. Another is 'That Time I Got Reincarnated as a Slime'. The protagonist is reborn in a new world and has to adapt and make his way, much like in 'isekai wa smartphone to tomo ni web novel'.
Well, if you like the idea of 'makikomarete isekai teni suru yatsu wa web novel', you might enjoy 'That Time I Got Reincarnated as a Slime'. In this web novel, the main character is reincarnated as a slime in another world and has to build his own community. 'No Game No Life' is also a great choice. The two main characters are transported to a world where everything is decided by games. These web novels, like the one in question, often explore the concept of being in a new world and the adventures and challenges that come with it.
It's a story about being transported to another world (isekai) with a smartphone. It likely combines elements of adventure, as the protagonist has to navigate this new world, and probably some unique plotlines thanks to the smartphone which is an unusual item to have in an isekai setting.
It's a story about being transported to another world (isekai) along with a smartphone. It likely involves the main character using the smartphone in the new world in various ways, like getting information, using apps, or communicating, which creates unique situations and adventures.
Since I don't know the exact nature of 'isekai demo bunan ni ikitai shoukougun web novel' in great detail, it's a bit tough to recommend exact similar ones. However, 'Sword Art Online' has some isekai - like elements where the characters are in a virtual world that has its own rules and challenges. Also, 'That Time I Got Reincarnated as a Slime' is an isekai where the protagonist has to figure out how to survive and thrive in a new world, which could potentially be related to the concept in the given web novel.
Since I don't know the exact nature of 'zettai ni yatte wa ikenai isekai novel', it's hard to give precise recommendations. However, there are many isekai novels out there. 'Overlord' is an isekai where the main character has to deal with ruling an otherworldly kingdom and has to abide by certain in - world rules. Another one could be 'That Time I Got Reincarnated as a Slime' which has unique world - building and rules for the characters to follow. These might have some similarities in terms of world - building and rule - following as the unknown novel.