My limited experience with in-wall speakers is that they have significantly reduced performance at a given price point compared to conventional speakers.
I have not heard any on-wall speakers (not sure if that's an option for you), but I'm skeptical they can match decent conventional speakers at a given price point. I'd be very interested with any experiences others have had with on-wall speakers.
If your only option is in-wall, in my opinion, matching will be the least of your worries. I'd try to find the best possible speakers within budget and let matching issues fall where they may (Full disclosure: I tend to think the importance of speaker matching is overstated in many cases, especially for mid and lower cost systems, but my view is probably a minority view)(In other words, take my opinion with a grain of salt).
I have 3 Aperion Intimus 6LCR in-wall speakers* and Aperion L6IC in-ceiling speakers in a 5.2 system in one room, and I have Aperion Verus Grand speakers in another room.** At one time I had identical Marantz AVRs and Oppo Blu ray players for both systems. I tried playing various Blu rays in both systems (I realize this is an apples to oranges comparison in terms of cost). There was a significant difference in sound quality.
The Aperion in-walls are definitely better than the in-wall speakers that were installed in the house when I bought it. Thus, I can say with certainty that there are worse in-wall speakers. The Aperion in-walls are also much better than the speakers in the TVs I've used in the system.
If you have very modest expectations, you might be happy with the Aperions or other in-wall speakers in that range. I'd recommend looking into building your own boxes if you go this route.
I have tried researching in-wall speakers to replace the existing in-wall speakers in an effort to get performance closer to that of free-standing speakers. I basically gave up. That's not to say they don't exist, but the effort exceedeed my patience threshold. Part of the problem in this quest has been my inability to find honest-to-goodness testing for in-wall speakers. Perhaps the data is out there and I've just missed it, but right now I'm not willing to spend a significant amount of money on an in-wall upgrade without having more data to go on.
*
https://www.audioholics.com/outdoor-speaker-reviews/aperion-audio-intimus-6-lcr-in-wall-speakers
**
https://www.audioholics.com/tower-speaker-reviews/verus-grand (I have an SVS PB13 Ultra sub, not the Aperion sub)