On Computer #1 (where the wallet with the address was created) the balance is correct (not 0.000000) and i have run the rescanblockchain command many times without success. Something is not working on this latter's versions of core btc. I don't want to use restore wallet from backup since it will compromise the security that a private kay offers.

Thank you for your time and help it is very impressive this day that forums still exist.
Computer #1 has created Wallet #1 and Wallet #2. Each wallet have created a new address using "Base58 (PSH-SegWit)".
Using the command dumpprivkey on Wallet #2 i got the private key for the public key (aka address) of this wallet. The public key (aka address) is a 3Mhxxxxx .
Next on Computer #2 i  created a new wallet using "Make Blank Wallet" check box enable. It confirmed the blocks and in deed i have an history of the transaction of this address but the available balance btc is 0.000000 . And when i press receive there is no address there, but when i press Window\Receiving addresses i can see 3 address
1. start with 15z xxxx
2. start with 3Mh xxxx and is the address i used to receive BTC on computer #1 on wallet #2 that has the exact address  i also used  dumpprivkey.
3. 3Nft xxxxx

Hi, do you think Bitcoin core is not secure? I am having difficulties finding that answer.
Example: A dedicated computer that 99,99% of the time is off. This computer has only one purpose, to keep a full node of btc and also has created 2 wallet #1 and #2. This computer for hardware has encrypted disk's with 2 set of raid 10 for backing up the backup wallet file. Extracting from disk this file has been tested successful.  Firewall has only one "allow" that is btc core everything else is blocked. And ofc both wallets are encrypted. So why a ledger USB is consider more secure then BTC core?

On this scenario there is a second computer also with btc core and also full node. This computer is always online (also has firewall that block everything except core btc). The purpose of this computer is to use the "importprivkey" of the wallet #2 that was created on this first computer so it can "receive" btc and then "send" them to wallet #1. Both computers dog have USB ports so the "importprivkey" is written down letter by letter.
But the "importprivkey" on the second computer do note restore the wallet #2.

Wallet was created on computer #1 and the "Descriptor Wallet" option was checked.
The Address was created "Base58 (PSH-SegWit)

Before using "importprivkey" on computer #2 a wallet with "Make Blank Wallet" ,check was created (i also tried a wallet with only "Descriptor Wallet" checked). Why this method do not restore the wallet and the address (public) on computer #2?

Thank you in advanced.