You can easily upload email addresses and send invites to players using The FA Matchday App
Please be aware this will not automatically send an invite to the players and that players must login by using their email address you have inputted and their FA Account Password - this can be set here: https://www.thefa.com/account/RequestPasswordReset
More guidance on inviting players can be found at: https://grassrootstechnology.freshdesk.com/support/solutions/articles/48000942801-how-to-invite-your-team-to-matchday