1. how safe this wallet ?
Its closed source so we cant assure its as safe as it should be. I personally wouldnt use them or at least wouldnt keep too much money in there. But they arent just an unknown random wallet, so I would say they are in the middle. Not the best option but also not a shit option.
2. am i really in control of my bitcoins or other coins ?
Yes. You have access to the seed and private keys. However, exporting them isnt as easy as other wallets because they want it to be as newbie-friendly as possible. And dealing with keys isnt very newbie-friendly.
See:
https://support.exodus.io/article/86-how-can-i-view-my-private-keys3. is the privay keys not stored in their server (because this wallet is managed) ?
No.