I would suggest you to copy a reference layout from /usr/share/X11/xkb/symbols/(prefered language)
and then see what keys do not fit. it is a plain text file, and looks something like the following
key <AD01> {[ q, Q, NoSymbol, NoSymbol, U211A ]};
key <AD02> {[ w, W ]};
key <AD03> {[ e, E, Greek_epsilon, eacute ]};
key <AD04> {[ r, R, Greek_rho, NoSymbol, U211D ]};
key <AD05> {[ t, T, Greek_theta, Greek_tau, NoSymbol, trademark ]};
key <AD06> {[ y, Y, dagger ]};
key <AD07> {[ u, U ]};
key <AD08> {[ i, I, integral, dintegral, Greek_iota ]};
key <AD09> {[ o, O, Greek_omega, Greek_OMEGA ]};
key <AD10> {[ p, P, Greek_pi, Greek_PI, Greek_psi, Greek_PSI ]};
key <AD11> {[ bracketleft, braceleft ]};
key <AD12> {[ bracketright, braceright ]};
key <AC01> {[ a, A, Greek_alpha, ae ]};
key <AC02> {[ s, S, Greek_sigma, Greek_SIGMA, Greek_finalsmallsigma ]};
key <AC03> {[ d, D, Greek_delta, Greek_DELTA ]};
key <AC04> {[ f, F, Greek_phi, Greek_PHI ]};
key <AC05> {[ g, G, Greek_gamma, Greek_GAMMA ]};
key <AC06> {[ h, H, Left, Left, Greek_eta, NoSymbol ]};
key <AC07> {[ j, J, Down, Down, NoSymbol, NoSymbol ]};
key <AC08> {[ k, K, Up, Up, Greek_kappa, NoSymbol ]};
key <AC09> {[ l, L, Right, Right, Greek_lambda, Greek_LAMBDA ]};
key <AC10> {[ colon, semicolon ]};
key <AC11> {[ apostrophe, quotedbl ]};
key <BKSL> {[ backslash, bar ]};
suppose you wanna switch q and e in this example, just switch them, and move this file to above location, and change layout from settings wherever you do (most de/wm have some place to change layout). I do this for greek symbols as you can see above, but you can do a lot like this.
for more details, check the following post https://lemmings.world/post/24385694
I see more activity on !onepiece@lemmy.world. Number of voters has not changed much, but definitely more posts/comments.