Similar with Bitcoin, you need to find wallet which support TRON (with it's token) and recovery from seed phrase. Multi-wallet such as Coinomi, Trustwallet and Atomic wallet support many popular altcoin, although all of them are closed source.
Yes, this is correct, but OP is asking for ways he can go about it even without using online wallets, but this will be difficult to attain or maybe not even possible for now. This would have been better if such wallets are like Electrum that can be used as cold storage and another as watch-only.
@miningsetup, the only correct way to restore wallets from a hardware wallet is to enter a seed into a new hardware wallet in case such a device breaks down, or you lose it. This would mean that you should buy 2 such devices and always keep one in case you need it - so although it is not a cheap solution, if you want maximum security you should avoid all other options.
This will be the best, simplest and the easiest method, but OP is insisting on airgapped wallet like Electrum. Also it depends, what if the hardware wallet is Trezor, and it was stolen? No passphrase used while generating the keys and addresses. If miningsetup (OP) later browsed about the safety of his/her keys but saw a link to the physical attack which can be carried out on Trezor to know the seed phrase which can be used to generate all the keys and access the funds. So, it depends on the situation, there are cases someone will not have any other option than to transfer the funds to another wallet which will demand for transaction fee.