IMHO most "home electronics" don't need inverter generators, will do nicely on a regular genset, at least I've never had any problems. When you think about it, the power that comes in from your utility isn't that pure, has spikes, dips, surges, etc. and your "home electronics" get along.
Not sure what you mean by transfer switch, to me that means something that just transfers from utility power to genset power and prevents backfeed from the genset to the utility lines and vice versa. "Usually," they"re used with a whole house generator powered by natural gas or propane so everything is automatic and are permanently installed and you do nothing when an outage occurs. Agree with Ron J, just run a couple of extension cords IF you want a 3KW inverter unit. To tie a transfer switch to that genset, not sure you could do it legally, you'll certainly end up with some very creative (Xpensive!!) wiring.
What you might consider is getting a 5000-5500W unit, put in a lockout switch and associated 30A breaker to feed your existing load center or breaker box. When an outage occurs, you open the main breaker which disconnects utility power, the "lockout" mechanically then allows you to close the 30A genset breaker, you then start the genset and connect. Obviously, you also have to open up all the "non critical" breakers in the box, leaving only the ones you need, e.g. Frig, Furnace, Freezer, a few lighting circuits. The load center typically would have a 200A main breaker and you're now limited to 30A so a lot of loads would have to go.
By all means, talk to an electrician who's familiar with gensets, lockouts, etc. otherwise you'll buy the wrong thing and have to get something else. There's a lot of info we can't possibly go into in a paragraph or two in a forum. e.g. Grounding, there would be two different schemes depending on running extension cords, vs interlocking a transfer switch.