^^ Both Zerodha Coin and Kuvera provide direct funds. I am not talking about that.
The main difference is that on Coin, funds are held in demat form. So you need a demat account like zerodha's to hold the funds and any additional investment in lump sum or SIP will have to be done through demat account. Basically, you are dependent on the demat account. So, if you want to stop using zerodha one day and you don't want to redeem your funds yet, you will either have to transfer your demat mutual funds to another demat account or pay fees to re materialize them into physical form. The fees for re-materialization are not trivial @ Rs 150 (+ CDSL charges) per every SIP in every fund you have ever made. If you have say 5 funds with monthly SIP done over 5 years before you want stop using zerodha, you will need to pay them 60 (SIP) x 5 (funds) x 150 = Rs 45000 and change your funds to physical form.
https://support.zerodha.com/categor...o/articles/how-to-re-materialize-mutual-funds
On Kuvera, the funds you buy will be just like when you buy them from individual AMC's, You are not dependent on Kuvera. If you want to stop using Kuvera, you can stop the SIPs setup in Kuvera and use the folio numbers to either deal with the AMC directly (including using their own portals) or migrate to another platform.
Leaving aside the demat vs non demat differences, there are several other differences between zerodha coin and kuvera.
1. Due to the way zerodha coin is integrated, the investment is always treated as lump sum on zerodha whether it is initial investment or subsequent SIP. All SIPs on zerodha are basically lumpsum which zerodha schedules for you. So, not only do you have to shell out a higher amount of Rs 5000 or Rs 10000 initially for lump sum, but also funds like Reliance Small Cap or SBI small cap that are currently not open for lump sum investment will not even be available for subscription in the web portal. When zerodha released their mobile app for coin, they rigged up a alternative solution that will allow you to subscribe to such funds from the mobile app, but even now, you cannot do this from the desktop portal. These funds are available for subscription in Kuvera. If lump sum is not available for a fund, it will just disable the lumpsum field. You can also start any fund as a SIP on kuvera.
Just to give an example of the differences, lets say you want to invest in 3 funds
MIRAE ASSET EMERGING BLUECHIP GROWTH DIRECT PLAN
HDFC SMALL CAP GROWTH DIRECT PLAN
FRANKLIN INDIA ULTRA SHORT BOND SUPER INSTITUTIONAL GROWTH DIRECT PLAN
On Zerodha desktop portal, you will not find the first fund at all since lump sum investment is not allowed for it presently. For the other two, you will need a capital of 5000 + 10000 = Rs 15000 to start investing. On Kuvera, you only need 1000 + 500 + 500 = Rs 2000 to start off with SIPs.
2. On Zerodha, there is no support for features like switching funds, STP or SWP which are available on Kuvera. Additionally, if you have MF investments done else where, you can import and manage them from Kuvera.