Your exodus wallet address is just an address on the Ethereum network. By virtue of having that, you 'have' a Polygon wallet of that same address already. By setting up metamask to connect to that address, first by default on Ethereum mainnet, then by adding the Polygon RPC info you will be able to connect to the Polygon network side of that wallet. You can theoretically already have or be receiving Polygon wrapped Ether on that address, by connecting metamask to it you will simply be viewing the contents and then be able to sign and interact with it to swap, etc.
Ether on the Ethereum network and Ether on the Polygon network are separate tokens. In order to convert one to the other you need to do this really intentional process called bridging, which takes time, effort and money. As such, just by connecting to a previously only Ethereum network wallet with a Polygon enabled wallet won't suddenly convert all the tokens in there to Polygon network tokens. Fact is, I've owned Ether on the same wallet address but on Ethereum, Polygon, Avalanche, Fantom and BSC. All require bridging to get from one to the other.
If you keep the Ethermine payouts on mainnet, whether you connect with exodus or metamask, those tokens will stay on mainnet. If you start getting them on Polygon, you'll need to connect with the wallet that has the Polygon RPC set up on it to see or interact with those tokens. Baseline within metamask, you need to switch the network to see the tokens on the respective networks. Also any tokens beyond Ether, you most of the time need to add the token in metamask to 'see' the quantity of that token within the wallet.
Another option to see your tokens, whether within metamask or with frankly any crypto address pretty much. You can browse to zapper.fi and put in your public address there and it will show you your wallet balances and break it down with balances on Ethereum, Polygon, FTM, Avax, BSC, or whatever network you have tokens on. You can also browse to zapper.fi within the metamask browser function. Zapper can be used to interact with your wallet, but baseline you can just use it as a viewer. Any tool that can interact with the network will ask you to connect and sign first, so you can always decline.
Well it sounds like to go forward and connect the metamask after doing the steps, to get L2 wrapped in the future at least, is easy enough. Its the getting it back out to sell that sounds daunting at this point.
I wonder what a typical fee to sell/get the tokens bridged might look like.
Ill say the gas fees havent hit 40 yet, 3 weeks in, so I raised it to 60 for now, may have to go a tad higher, but if im not misunderstanding, even say a 60 fee isnt bad and doesnt seem to matter how much ether you are transferring (so say $7 for instance). If thats every 2 weeks, oh well i guess. However, 2 days after 60 still waiting, might need to go up a few notches if im sticking with that method.