I would recommend with hesitations. Namely, you need to know what you're getting into. It is neither a pokemon copy nor completely its own thing. You get the sense throughout the game that the developers never really decided / planned what they wanted. In the beginning, there are numerous pokemon references -- all the way down to starting the game as a ten year old. (That's something pokemon should have also trashed a long time ago). The battle mechanics are largely broken--only the attack stat matters. About 90 percent of the creatures have poor defense, so you can KO them with one or two moves. The type design has a real weakness with not making a nexomon resist its own typing. A fire nexomon can be hit with a fire move and its like hitting with it a neutral normal type move. The battle/skills seem like they were designed by an inexperienced pokemon player -- a person who only use damage moves with strongest power. Status moves (i.e. defense raising, poisoning moves, etc) will not usually put you at any advantage.
The biggest weakness in the storyline is that you can never tell what's going happen next on screen -- if you go into the next screen-- are you going to encounter some story event? is it going to derail you for a while when you just wanted to grind or catch nexomon? is it going to block out certain areas that you won't be able to access for some time (or ever again) ?
The lack of a map / routes is disorienting; especially if you use to guides to try to catch all the nexomon.
The "post-game" is not really post at all; it's just "post pokemon champion". The post-game is largely a waste of time and also points to undecided game direction by the creators. I think the "reborn" aspect should have been introduced earlier into the game and made integral to it. All of the nexomons can be found in the main storyline if you are patient enough. The developers could have the cut some of the nexomon first forms from the main plot and made it so you could only find them in the nexoworld or by having the evolved forms reborn.
It also seems like the game was developed with the idea that the player would not change their party after the initial areas. You can make any creature reborn, but by the end of the game why would you bother with any team other than your champion team? Especially when the post game is simply defeat the bad guy again.
The rarity types of nexomon are not related to their rarity/frequency of being found. In my experience, the hardest category to find were the "uncommon" nexomon. The 'rarity' labels are more like classes of their strength. It's really deterministic that the best team, other than legendaries, is supposed to be all mega rares/starters. All creatrues below that are noticeably weaker. And the common nexomon are just laughably weak.
Things I like -- levelling up heals the nexomon; I like the nexomon designs (not the names). I like that the designs escape some of the "environment" trap that pokemon finds itself in. For example, in pokemon, you expect the jungle to be filled with grass types. The jungle in nexomon has more than that. Fish nexomon can be types other water. There's a fish that's a wind type and a bird that's a grass type. That's really cool. Pokemon hasn't taken that direction of creativity.

If your full intent is to play pokemon, just buy pokemon. Nexomon will disappoint.
If you want to buy a video game for someone who likes pokemon, don't buy this. At the best, you'll become the well-meaning but ill-informed friend/parent/etc. At the worst, you'll look cheap.
If you are looking for a monster catching game that specifically isn't pokemon, don't buy nexomon.
If you are familiar with pokemon, but you're not overly glued to it. Maybe you'll like this. At least to pass the time.
This is a game you would buy for yourself. I would not buy it for anyone else. Just like that tshirt that you only wear at home, but refuse to wear in public.

Honestly a great game until the Post game grind showed up. They should've ended the story instead of adding more content that's tedious and not worth the grind. Start middle End that's all they need. Play if you enjoy monster capture games but the Post game grind can be left out honestly.

Nexomon was a game I wasn't sure how I'd feel about, both because visually it really just gives mobile graphics and gameplay vise it feels very much like Pokemon but not Pokemon, however after putting in 45 hours or so I have to say it was kinda fun!

I really loved the designs of the creatures, as well as the overall vibes of the world itself. I wasn't too big on the fact that we had five massive annoying enemies that would constantly push themselves down our throat and make themselves known and just bleh. It was very frustrating, I have to say it was not a fun part of the story.

I also liked a lot of the designs, some I was meh on but most were really creative and very well done, even for being a Pokemon-like.

The combat was alright, the stamina system just I'm not too big of a fan of in this way, where it's a second resource that doesn't recharge after battles, as well as I did like having everything refresh on level up, which was nice. I do wish the EXP share was given earlier, but that's just me.

I also didn't like how every, single status condition was effectively a stun, how it was very annoying and just overall not fun to deal with, like constrict and stun and frozen all being a way to prevent you from moving just. They could've been a tad bit different, but oh well it was something that could've been fixed in an update.

I liked the capture tool, it's kinda a cool X looking thing, though I did wish there was some variation in the types of allow you to get better odds when catching.

I'd recommend this game though I'd only do so when on sale, definitely fun but only if you want to try new creature collectors.